Arduino 1.6.x compiler options...

I'd noticed recently that since I'd upgraded the Arduino IDE to 1.6.x, some programs compiled and were smaller than they used to be. Great!

... the also don't run so fast... not so great.

After some googling around, the compiler options for optimisation had been changed.

So if you need something to compile and run quickly, you can.

Here's how to change it...

Navigate your way to the default Arduino directory in program files, and locate the platform.txt file

On my windows box, it's at C:\Program Files (x86)\Arduino\hardware\arduino\avr
On my Ubuntu box it's Home\Downloads\arduino-1.6.12\hardware\arduino\avr  (Why did I ./install.sh from the downloads folder!!!)

there's also one in the \hardware directory itself. That's not it!

Mine looks like this :

# Arduino AVR Core and platform. # ------------------------------ # # For more info: # https://github.com/arduino/Arduino/wiki/Arduino-IDE-1.5-3rd-party-Hardware-specification name=Arduino AVR Boards version=1.6.14 # AVR compile variables # --------------------- compiler.warning_flags=-w compiler.warning_flags.none=-w compiler.warning_flags.default= compiler.warning_flags.more=-Wall compiler.warning_flags.all=-Wall -Wextra # Default "compiler.path" is correct, change only if you want to override the initial value compiler.path={runtime.tools.avr-gcc.path}/bin/ compiler.c.cmd=avr-gcc compiler.c.flags=-c -g -Os {compiler.warning_flags} -std=gnu11 -ffunction-sections -fdata-sections -MMD -flto -fno-fat-lto-objects compiler.c.elf.flags={compiler.warning_flags} -Os -flto -fuse-linker-plugin -Wl,--gc-sections compiler.c.elf.cmd=avr-gcc compiler.S.flags=-c -g -x assembler-with-cpp -flto compiler.cpp.cmd=avr-g++ compiler.cpp.flags=-c -g -Os {compiler.warning_flags} -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -MMD -flto compiler.ar.cmd=avr-gcc-ar compiler.ar.flags=rcs compiler.objcopy.cmd=avr-objcopy compiler.objcopy.eep.flags=-O ihex -j .eeprom --set-section-flags=.eeprom=alloc,load --no-change-warnings --change-section-lma .eeprom=0 compiler.elf2hex.flags=-O ihex -R .eeprom compiler.elf2hex.cmd=avr-objcopy compiler.ldflags= compiler.size.cmd=avr-size # This can be overridden in boards.txt build.extra_flags= # These can be overridden in platform.local.txt compiler.c.extra_flags= compiler.c.elf.extra_flags= compiler.S.extra_flags= compiler.cpp.extra_flags= compiler.ar.extra_flags= compiler.objcopy.eep.extra_flags= compiler.elf2hex.extra_flags= # AVR compile patterns # -------------------- ## Compile c files recipe.c.o.pattern="{compiler.path}{compiler.c.cmd}" {compiler.c.flags} -mmcu={build.mcu} -DF_CPU={build.f_cpu} -DARDUINO={runtime.ide.version} -DARDUINO_{build.board} -DARDUINO_ARCH_{build.arch} {compiler.c.extra_flags} {build.extra_flags} {includes} "{source_file}" -o "{object_file}" ## Compile c++ files recipe.cpp.o.pattern="{compiler.path}{compiler.cpp.cmd}" {compiler.cpp.flags} -mmcu={build.mcu} -DF_CPU={build.f_cpu} -DARDUINO={runtime.ide.version} -DARDUINO_{build.board} -DARDUINO_ARCH_{build.arch} {compiler.cpp.extra_flags} {build.extra_flags} {includes} "{source_file}" -o "{object_file}" ## Compile S files recipe.S.o.pattern="{compiler.path}{compiler.c.cmd}" {compiler.S.flags} -mmcu={build.mcu} -DF_CPU={build.f_cpu} -DARDUINO={runtime.ide.version} -DARDUINO_{build.board} -DARDUINO_ARCH_{build.arch} {compiler.S.extra_flags} {build.extra_flags} {includes} "{source_file}" -o "{object_file}" ## Create archives # archive_file_path is needed for backwards compatibility with IDE 1.6.5 or older, IDE 1.6.6 or newer overrides this value archive_file_path={build.path}/{archive_file} recipe.ar.pattern="{compiler.path}{compiler.ar.cmd}" {compiler.ar.flags} {compiler.ar.extra_flags} "{archive_file_path}" "{object_file}" ## Combine gc-sections, archives, and objects recipe.c.combine.pattern="{compiler.path}{compiler.c.elf.cmd}" {compiler.c.elf.flags} -mmcu={build.mcu} {compiler.c.elf.extra_flags} -o "{build.path}/{build.project_name}.elf" {object_files} "{build.path}/{archive_file}" "-L{build.path}" -lm ## Create output files (.eep and .hex) recipe.objcopy.eep.pattern="{compiler.path}{compiler.objcopy.cmd}" {compiler.objcopy.eep.flags} {compiler.objcopy.eep.extra_flags} "{build.path}/{build.project_name}.elf" "{build.path}/{build.project_name}.eep" recipe.objcopy.hex.pattern="{compiler.path}{compiler.elf2hex.cmd}" {compiler.elf2hex.flags} {compiler.elf2hex.extra_flags} "{build.path}/{build.project_name}.elf" "{build.path}/{build.project_name}.hex" ## Save hex recipe.output.tmp_file={build.project_name}.hex recipe.output.save_file={build.project_name}.{build.variant}.hex ## Compute size recipe.size.pattern="{compiler.path}{compiler.size.cmd}" -A "{build.path}/{build.project_name}.elf" recipe.size.regex=^(?:\.text|\.data|\.bootloader)\s+([0-9]+).* recipe.size.regex.data=^(?:\.data|\.bss|\.noinit)\s+([0-9]+).* recipe.size.regex.eeprom=^(?:\.eeprom)\s+([0-9]+).* ## Preprocessor preproc.includes.flags=-w -x c++ -M -MG -MP recipe.preproc.includes="{compiler.path}{compiler.cpp.cmd}" {compiler.cpp.flags} {preproc.includes.flags} -mmcu={build.mcu} -DF_CPU={build.f_cpu} -DARDUINO={runtime.ide.version} -DARDUINO_{build.board} -DARDUINO_ARCH_{build.arch} {compiler.cpp.extra_flags} {build.extra_flags} {includes} "{source_file}" preproc.macros.flags=-w -x c++ -E -CC recipe.preproc.macros="{compiler.path}{compiler.cpp.cmd}" {compiler.cpp.flags} {preproc.macros.flags} -mmcu={build.mcu} -DF_CPU={build.f_cpu} -DARDUINO={runtime.ide.version} -DARDUINO_{build.board} -DARDUINO_ARCH_{build.arch} {compiler.cpp.extra_flags} {build.extra_flags} {includes} "{source_file}" -o "{preprocessed_file_path}" # AVR Uploader/Programmers tools # ------------------------------ tools.avrdude.path={runtime.tools.avrdude.path} tools.avrdude.cmd.path={path}/bin/avrdude tools.avrdude.config.path={path}/etc/avrdude.conf tools.avrdude.upload.params.verbose=-v tools.avrdude.upload.params.quiet=-q -q tools.avrdude.upload.params.noverify=-V tools.avrdude.upload.pattern="{cmd.path}" "-C{config.path}" {upload.verbose} {upload.verify} -p{build.mcu} -c{upload.protocol} -P{serial.port} -b{upload.speed} -D "-Uflash:w:{build.path}/{build.project_name}.hex:i" tools.avrdude.program.params.verbose=-v tools.avrdude.program.params.quiet=-q -q tools.avrdude.program.params.noverify=-V tools.avrdude.program.pattern="{cmd.path}" "-C{config.path}" {program.verbose} {program.verify} -p{build.mcu} -c{protocol} {program.extra_params} "-Uflash:w:{build.path}/{build.project_name}.hex:i" tools.avrdude.erase.params.verbose=-v tools.avrdude.erase.params.quiet=-q -q tools.avrdude.erase.pattern="{cmd.path}" "-C{config.path}" {erase.verbose} -p{build.mcu} -c{protocol} {program.extra_params} -e -Ulock:w:{bootloader.unlock_bits}:m -Uefuse:w:{bootloader.extended_fuses}:m -Uhfuse:w:{bootloader.high_fuses}:m -Ulfuse:w:{bootloader.low_fuses}:m tools.avrdude.bootloader.params.verbose=-v tools.avrdude.bootloader.params.quiet=-q -q tools.avrdude.bootloader.pattern="{cmd.path}" "-C{config.path}" {bootloader.verbose} -p{build.mcu} -c{protocol} {program.extra_params} "-Uflash:w:{runtime.platform.path}/bootloaders/{bootloader.file}:i" -Ulock:w:{bootloader.lock_bits}:m tools.avrdude_remote.upload.pattern=/usr/bin/run-avrdude /tmp/sketch.hex {upload.verbose} -p{build.mcu} # USB Default Flags # Default blank usb manufacturer will be filled in at compile time # - from numeric vendor ID, set to Unknown otherwise build.usb_manufacturer="Unknown" build.usb_flags=-DUSB_VID={build.vid} -DUSB_PID={build.pid} '-DUSB_MANUFACTURER={build.usb_manufacturer}' '-DUSB_PRODUCT={build.usb_product}'

Now I'd rename this to platform.old, so it's there if we screw it up, or wish to revert to slower, but more space-efficient code.

Now, open this file in your favorite text editor (mine's Notepad++ on windows) and do a find and replace on all instances of -Os (that's the letter O) and replace it with -O2 (again, the letter O) There are 3 instances of it in my file...

Bingo, save that as platform.txt in the directory, and you're done.

Here's my modified file...

# Arduino AVR Core and platform. # ------------------------------ # # For more info: # https://github.com/arduino/Arduino/wiki/Arduino-IDE-1.5-3rd-party-Hardware-specification name=Arduino AVR Boards version=1.6.14 # AVR compile variables # --------------------- compiler.warning_flags=-w compiler.warning_flags.none=-w compiler.warning_flags.default= compiler.warning_flags.more=-Wall compiler.warning_flags.all=-Wall -Wextra # Default "compiler.path" is correct, change only if you want to override the initial value compiler.path={runtime.tools.avr-gcc.path}/bin/ compiler.c.cmd=avr-gcc compiler.c.flags=-c -g -O2 {compiler.warning_flags} -std=gnu11 -ffunction-sections -fdata-sections -MMD -flto -fno-fat-lto-objects compiler.c.elf.flags={compiler.warning_flags} -O2 -flto -fuse-linker-plugin -Wl,--gc-sections compiler.c.elf.cmd=avr-gcc compiler.S.flags=-c -g -x assembler-with-cpp -flto compiler.cpp.cmd=avr-g++ compiler.cpp.flags=-c -g -O2 {compiler.warning_flags} -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -MMD -flto compiler.ar.cmd=avr-gcc-ar compiler.ar.flags=rcs compiler.objcopy.cmd=avr-objcopy compiler.objcopy.eep.flags=-O ihex -j .eeprom --set-section-flags=.eeprom=alloc,load --no-change-warnings --change-section-lma .eeprom=0 compiler.elf2hex.flags=-O ihex -R .eeprom compiler.elf2hex.cmd=avr-objcopy compiler.ldflags= compiler.size.cmd=avr-size # This can be overridden in boards.txt build.extra_flags= # These can be overridden in platform.local.txt compiler.c.extra_flags= compiler.c.elf.extra_flags= compiler.S.extra_flags= compiler.cpp.extra_flags= compiler.ar.extra_flags= compiler.objcopy.eep.extra_flags= compiler.elf2hex.extra_flags= # AVR compile patterns # -------------------- ## Compile c files recipe.c.o.pattern="{compiler.path}{compiler.c.cmd}" {compiler.c.flags} -mmcu={build.mcu} -DF_CPU={build.f_cpu} -DARDUINO={runtime.ide.version} -DARDUINO_{build.board} -DARDUINO_ARCH_{build.arch} {compiler.c.extra_flags} {build.extra_flags} {includes} "{source_file}" -o "{object_file}" ## Compile c++ files recipe.cpp.o.pattern="{compiler.path}{compiler.cpp.cmd}" {compiler.cpp.flags} -mmcu={build.mcu} -DF_CPU={build.f_cpu} -DARDUINO={runtime.ide.version} -DARDUINO_{build.board} -DARDUINO_ARCH_{build.arch} {compiler.cpp.extra_flags} {build.extra_flags} {includes} "{source_file}" -o "{object_file}" ## Compile S files recipe.S.o.pattern="{compiler.path}{compiler.c.cmd}" {compiler.S.flags} -mmcu={build.mcu} -DF_CPU={build.f_cpu} -DARDUINO={runtime.ide.version} -DARDUINO_{build.board} -DARDUINO_ARCH_{build.arch} {compiler.S.extra_flags} {build.extra_flags} {includes} "{source_file}" -o "{object_file}" ## Create archives # archive_file_path is needed for backwards compatibility with IDE 1.6.5 or older, IDE 1.6.6 or newer overrides this value archive_file_path={build.path}/{archive_file} recipe.ar.pattern="{compiler.path}{compiler.ar.cmd}" {compiler.ar.flags} {compiler.ar.extra_flags} "{archive_file_path}" "{object_file}" ## Combine gc-sections, archives, and objects recipe.c.combine.pattern="{compiler.path}{compiler.c.elf.cmd}" {compiler.c.elf.flags} -mmcu={build.mcu} {compiler.c.elf.extra_flags} -o "{build.path}/{build.project_name}.elf" {object_files} "{build.path}/{archive_file}" "-L{build.path}" -lm ## Create output files (.eep and .hex) recipe.objcopy.eep.pattern="{compiler.path}{compiler.objcopy.cmd}" {compiler.objcopy.eep.flags} {compiler.objcopy.eep.extra_flags} "{build.path}/{build.project_name}.elf" "{build.path}/{build.project_name}.eep" recipe.objcopy.hex.pattern="{compiler.path}{compiler.elf2hex.cmd}" {compiler.elf2hex.flags} {compiler.elf2hex.extra_flags} "{build.path}/{build.project_name}.elf" "{build.path}/{build.project_name}.hex" ## Save hex recipe.output.tmp_file={build.project_name}.hex recipe.output.save_file={build.project_name}.{build.variant}.hex ## Compute size recipe.size.pattern="{compiler.path}{compiler.size.cmd}" -A "{build.path}/{build.project_name}.elf" recipe.size.regex=^(?:\.text|\.data|\.bootloader)\s+([0-9]+).* recipe.size.regex.data=^(?:\.data|\.bss|\.noinit)\s+([0-9]+).* recipe.size.regex.eeprom=^(?:\.eeprom)\s+([0-9]+).* ## Preprocessor preproc.includes.flags=-w -x c++ -M -MG -MP recipe.preproc.includes="{compiler.path}{compiler.cpp.cmd}" {compiler.cpp.flags} {preproc.includes.flags} -mmcu={build.mcu} -DF_CPU={build.f_cpu} -DARDUINO={runtime.ide.version} -DARDUINO_{build.board} -DARDUINO_ARCH_{build.arch} {compiler.cpp.extra_flags} {build.extra_flags} {includes} "{source_file}" preproc.macros.flags=-w -x c++ -E -CC recipe.preproc.macros="{compiler.path}{compiler.cpp.cmd}" {compiler.cpp.flags} {preproc.macros.flags} -mmcu={build.mcu} -DF_CPU={build.f_cpu} -DARDUINO={runtime.ide.version} -DARDUINO_{build.board} -DARDUINO_ARCH_{build.arch} {compiler.cpp.extra_flags} {build.extra_flags} {includes} "{source_file}" -o "{preprocessed_file_path}" # AVR Uploader/Programmers tools # ------------------------------ tools.avrdude.path={runtime.tools.avrdude.path} tools.avrdude.cmd.path={path}/bin/avrdude tools.avrdude.config.path={path}/etc/avrdude.conf tools.avrdude.upload.params.verbose=-v tools.avrdude.upload.params.quiet=-q -q tools.avrdude.upload.params.noverify=-V tools.avrdude.upload.pattern="{cmd.path}" "-C{config.path}" {upload.verbose} {upload.verify} -p{build.mcu} -c{upload.protocol} -P{serial.port} -b{upload.speed} -D "-Uflash:w:{build.path}/{build.project_name}.hex:i" tools.avrdude.program.params.verbose=-v tools.avrdude.program.params.quiet=-q -q tools.avrdude.program.params.noverify=-V tools.avrdude.program.pattern="{cmd.path}" "-C{config.path}" {program.verbose} {program.verify} -p{build.mcu} -c{protocol} {program.extra_params} "-Uflash:w:{build.path}/{build.project_name}.hex:i" tools.avrdude.erase.params.verbose=-v tools.avrdude.erase.params.quiet=-q -q tools.avrdude.erase.pattern="{cmd.path}" "-C{config.path}" {erase.verbose} -p{build.mcu} -c{protocol} {program.extra_params} -e -Ulock:w:{bootloader.unlock_bits}:m -Uefuse:w:{bootloader.extended_fuses}:m -Uhfuse:w:{bootloader.high_fuses}:m -Ulfuse:w:{bootloader.low_fuses}:m tools.avrdude.bootloader.params.verbose=-v tools.avrdude.bootloader.params.quiet=-q -q tools.avrdude.bootloader.pattern="{cmd.path}" "-C{config.path}" {bootloader.verbose} -p{build.mcu} -c{protocol} {program.extra_params} "-Uflash:w:{runtime.platform.path}/bootloaders/{bootloader.file}:i" -Ulock:w:{bootloader.lock_bits}:m tools.avrdude_remote.upload.pattern=/usr/bin/run-avrdude /tmp/sketch.hex {upload.verbose} -p{build.mcu} # USB Default Flags # Default blank usb manufacturer will be filled in at compile time # - from numeric vendor ID, set to Unknown otherwise build.usb_manufacturer="Unknown" build.usb_flags=-DUSB_VID={build.vid} -DUSB_PID={build.pid} '-DUSB_MANUFACTURER={build.usb_manufacturer}' '-DUSB_PRODUCT={build.usb_product}'

You can now enjoy faster, but fatter sketches!

.. or not!

NAD 5425 CD player - no display

Just a quick one. This delightful NAD 5425 CD player.

Arrived skipping / not reading discs and no display.


Skipping and intermittently not reading discs was an easy fix, a quick clean up of the optics with an airduster, and very careful cleaning of the lens (DON'T USE IPA HERE! - it can damage the optical coating on the lens. It's easy just to breathe on it, and give it a gentle wipe with something lint-free). That had it playing even the most mangy looking disc!




No display?



Let investigate...

The main board is removed ....









.. and the display cowl removed (there's a couple of screws underneath, and a plastic clip.)












... and an open-circuit incandescent lamp is the culprit...










To improve reliability, and LED and 1K limiting resistor is fixed in place. Note the capton tape to insulate it electrically from the links on the board below. Anode (+ve) is to the right in this picture.

The LED I chose was a wide-angle, warm white LED, which I hope will match the original incandescent lamp closely.







... which is does nicely!














I've not tried these wide-angle LEDs before. They're quite good. These are both warm white examples, although they differ in colour slightly! You can clearly see the focussed "beam" coming from the right hand LED, and the much more diffuse spread of light from the left hand "wide-angle" LED.





Job done. Another saved from landfill!

Leak 2100 amplifier repairs.

A while back, David (from the motherland) donated some stuff to the cause.

This Leak amplifier was amongst the things he dropped off...

Dating from around 1974, and mostly valueless... eBay prices these at about £30 at the time of writing.

Still, there's no point in it just sitting in a pile...






It's been through the wars a bit, but that's OK. I need something to practise my veneering skills on, for a forthcoming turntable project, so this may do as a test bed...










Typical 70's construction.

I'd labelled the amp up "Hums" ....










There's something unpleasant oozing out of the top of the positive rail smoothing cap... It's a 6,800uF 40V part....










... I have some 10,000uF 63V parts, which are slightly fatter, but much shorter. The fit in the clips OK, so they'll do....

Powering up instantly blows both 5A fuses on the main board. You can see in the photo, I've lifted R3 and R5 on the small vertical PCB. This is the protection board. It's purpose in life is to blow fuses by shorting out the supply rails with a triac in the event of there being more that 0.5VDC on the speaker outputs. A sort of crowbar circuit.

Powering up again, with new fuses and checking the speaker outputs (with no speakers attached) for DC shows everything in order.

R3 and R5 are soldered back into position and power is applied again. All is well. I wonder if one rail came up before the other due to the new/larger caps?

I check round the caps on the main board for ESR. Remarkably, they all check out OK. Every last one of them! I even checked the calibration on the ESR meter because I doubted it!


The power indicator lamp on the front doesn't work, because, well... it's missing. I'll make up some white LED's to go in...











I had a short length of LED strip left over from when I fitted some lighting in my kitchen, so I cut off a short length. The voltage supply for the lamps is half wave rectified, with no smoothing. It peaks at around 20 volts, so I added a 470 ohm resistor to limit the current a bit, and added 100uF to smooth the supply a bit, so the LED's don't flicker.




I removed the original lamp holder, and fixed the strip in place with a spot of hot-melt.

Looks good....








After a prolonged test in the workshop, the amp remains well-mannered, and sounds decent. It's quiet and produces around 30 watts into 8 ohms. I'm actually quite taken with it, so much so, I'm going to put it in the main hifi set up for a bit.. one issue though... the input sensitivity. It's a tiny 140mV for line inputs. We'll need to fit an attenuator on the input I intend to use for the CD player. Thankfully there's an attenuator switch fitted to the Tuner input, which is switched on the back for two different levels. Looking at the circuit, my calculations show it'll do as it stands. Good news!

Now to make up some 5-pin DIN to RCA leads, and order some veneer!

Talking of 5-pin DIN plugs... this Leak doesn't quite follow convention....


1 is Right input
2 is GND
3 is Left input.


4 is Right output for Tape/cassette
5 is Left output for Tape/cassette....

Wharfdale Airedale SP2 Speakers.

Well, there appears to scant information on the web about these wonderful speakers, so I thought I'd share some pictures of mine up. Sadly they're not going to be with me long, as they're not exactly wife-friendly, due to there huge size (H 88cm W 46.5cm D 44cm!)

They were Wharfdale's top-of-the-range speakers in the mid 70's.

Tweeter. I saw a thread on a forum that said these were ribbon tweeters, but I don't think so. How do you make a round ribbon?

Upper mid-range, with felt suspension...

4" mid-range, again with felt suspension.












... and the 10" bass driver, with rubber suspension.

They sound fantastic, and are in really good condition. Speakers of this age generally start to have problems with the suspension breaking up, but these are just great. Sadly they're just too big...so it's off to eBay with them :(

Quad 405-2 Amplifier - restoration.

The next part of the Quad series. The mighty 405-2 power amplifier. Famed for it's current dumping design.

This amplifier was made around 1984, as some of the RCA transistors are nicely dated.

This amplifier isn't performing too well. It's distorting, and humming slightly.
















The amplifier is nicely laid out, although I'm not too impressed with the safety earthing arrangements. The earth is taken to a point a long way from where the supply is grounded. This can exacerbate ground loop issues. This amp hums, and I also have a friend whose 405 hums quite badly. Could this be the cause?





The ground connections to the speakers are also made separately...










Removal of each amplifier board is made easy by removing the two rubber bungs thoughtfully supplied by Quad, which allow insertion of a long screwdriver to gain access to the lower screws securing each board to the large heatsink at the front. The boards fitted to this amplifier are rev. 7 boards, and are also fitted with voltage limiters, so It's suitable for driving Quad's ESL speakers.







First inspection of the amplifier show some of the Red cased electrolytic capacitors are showing signs of age, looking a bit "sweaty" and having cracked cases.

Two of the caps in my amp (C17 & C2) are bi-polar, which is a pain. C2 can be replaced by a conventional electrolytic, with the positive side to ground, but C17 must remain bi-polar... which is a pain , because they're awful and I don't stock any!









Low-and-behold, C5, a 6.3V Electrolytic is leaking and has turned the pin green!

Both of the large 10,000uF capacitors test like new, so they can stay.
















I decided, in an effort to mitigate any ground-loop issues, to ground the speakers and the mains safety earth back to the same point.








So after a blanket change of the capacitors, the amplifier powers up, and tests very well, with no adverse behaviour, and there's certainly no perceivable hum! All the unpleasant distortion has gone :)

There are quite a few websites detailing modifications to this amplifier, in particular Keith Snook's site (here), I did think about implementing some of these modifications, but I'm rather taken with it in stock form, so it will stay like that!

Guilty as changed, your honour ! (There's a joke in there!)

The Nikon D3100 camera disaster, a thank you, and a recommendation.

Back when the weather was fine, I was out in the garden taking some nice photos at a barbecue party. All was well until I dropped my beloved Nikon D3100 camera onto concrete.... The lens developed a bit of lateral play in the zoom, but it was still working OK....

... until it stopped auto-focusing a couple of weeks later ...

Nothing to it, but to investigate.

I proved the lens was at fault by borrowing another lens from a friend. The camera body was fine...

So I stripped the lens down... sadly I don't have any pictures.

There was a bush missing, which was causing the play, so I fabricated a new one and fitted it. Lateral play issue resolved.

I managed to find the old bush, in two parts, jammed up against the primary lens cover.

 Auto focus was still not working... damn.

At this point I decided to get another lens.

Whilst looking on eBay, I spotted a replacement lens. The description was perfect, but it showed pictures of a Cannon lens. I emailed the seller, who replied, thanking me for spotting the error, and they had corrected the listing. By this stage I had purchased another lens from another dealer.

The box arrived after a few days wait..... Now I'd done a bit of research on the lens before I hit the buy button. Nikon's website informed me the lens was compatible "with all DX cameras"... and mine's a DX camera....

... what they didn't say was the auto-focus wasn't compatible with all DX cameras (well, they do, but you've really got to go looking for the information!)... boo. I needed an AF-S lens, and the new one was AF-P.

I emailed the dealer that had originally listed the correct lens wrongly on eBay (the Canon one) asking if they'd part-ex my new, but incorrect lens for the right one.

They emailed back straight away, and said they'd be happy to swap it for me anyway (despite the fact I never bought it from them!) Now that's service. I suppose I could have sent the wrong lens back, but that would have been hassle....

As a deal wasn't done on eBay, I can't even leave them positive feedback....

So thank you eBay seller alldigital0869. (Shop is called The Photographers Bag link here.) You're the best.

The two recommendations are :

1) Don't drop your camera.
2) Use alldigital0869 on eBay with complete confidence!

There's some posts in the pipe-line with photo's taken with my old Samsung camera, but, rest-assured the Nikon is back!

Quad 44 pre-amp. Minor restoration, and some sensible modifications

Along with the FM tuner I got last week, I also obtained a matching 44 pre-amp and a 405-2 power amplifier. Very nice kit!

The 44 is a very interesting pre-amp. It's got a lovely design of tone control. Quad went their own way with adding tone controls, and made theirs with 3 tone filters and an adjustable slope control.

The look of the thing is even unique.


The pre-amp has a flexible card system. Each input is selected by a CD4066 switch, which connects the selected card. This unit has the standard line-up of "Radio", "Disc" for a Moving magnet cartridge (an MC card is/was available), a CD/AUX card and two tape loops. Excellent.




Not only that, but the Disc card allows differing gains to be selected to accommodate for most carts, and switchable capacitance load too. The tape loops are similarly configurable for level and impedance. Nice....












This later "MKII" model has a re-designed main board and ALPS pots....










Issues....

CD4066? Known for introducing distortion into the signal path. Thankfully Maxim produce the MAX4066. A much better specified, and pin for pin compatible device....

So, before I start, let's make a baseline measurement of THD (Total harmonic distortion) at 1KHz....  0.059% on the CD/AUX channel.

Not too shabby....







Out with the old, and in with the new....

All 4 ICs are changed.








Whilst I'm in there I evict the Red electrolytics, as they're know to fail, although these all read OK.

Let's have a look at the disc card...

It consists of TL071 op-amps.... which are mediocre. I'll swap them out for some better NE5534, which should lower noise a bit, as well as distortion. These are the better NE5534's with 18V/uS slew rate.







... and here is the main issue for me....

The CD/Aux card....

300mV? ... 300mV!!!!

Since when?

Most CD players put out at least a volt...

All this means practically, is we'll need to turn our volume control down everytime we switch to CD. An inconvenience. We *may* overload the input.

I've seen some CD players output as much as 2V, so 300mV is not going to cut it....

It's also originally fitted with a TL072, which I'll change for an NE5532..

I do some googling, and there's various recommendations about changing the resistors in the feedback loop of the card to reduce the gain to unity... but none of the modifications seem to  relate to the input card I have fitted, an M12815:1. I don't have a schematic, so I sketch one out....

... well, it's already a unity-gain amplifier!

So, what to do? I could trace the signal through and change the gain on the main board, but that will leave me with the same discrepancy when switching between CD and disc or radio.... Nothing for it but to add a bit of attenuation in.


Simply adding a 180 ohm resistor across the existing 820 ohm resistor will divide the voltage down to a more respectable level.





... and it's easy to implement...

Don't forget to do both channels.













So after all out mods... how does it measure?

... The THD has dropped to 0.014%....


How does it sound? Noticeably quieter (noise-wise!), but to my cloth ears, I can't really tell much difference in the distortion.

Right, now to the 405-2 Power amp!

Watch this space....

Quad FM4 drifting and amnesia.

So here it is, the wonderful Quad FM4 tuner. A thing of beauty.

This one is an early example and dates from around 1982-83.

It's suffering from amnesia (it won't store stations after a power off) and even in manual tuning the frequency falls after a few minutes use....

Let's see what's wrong...


It's a simple layout. First off the memory battery is shot, and leaking. Thankfully it hasn't damaged the board, and a replacement (Varta Mempac 4.8V, 150mAH) restores it's memory... as for the frequency drift...

The tuner operates by a voltage controlled tuner, there's no synthesiser in here! The memories work by digitising the tuning voltage and storing it, recreating it with a DAC when the preset is selected. The fault is the tuning voltage is falling off. Turns out it's our best friend (and foe!) the elctrolytic capacitor. The guily parties are all 100uF 6.3V types. I changed them all. I dislike 6.3V electrolytics, they seem to give more problems than higher voltage types, even though they were all working well within voltage limits. Perhaps it's their physical size that makes manufacture difficult? ....  (perhaps they just don't like me?!)

Zoom in on the picture and you can see where they are physically leaking.

This cured the drift, but one of the 220uF 16V caps that smoothes the regulated 12V supply looked like it had seen better days, so I changed both of those too... even though they measured OK. One is adjacent to the 12V regulator transistor, which runs a little hot. Never an ideal location for an electrolytic!


Sound quality is great, and will give many years of service now!

Nakamichi RX-202E

This arrived in the workshop.

It's a Nakamichi RX-202E Unidirectional Auto-reverse cassette recorder. A thing of rare beauty and quality. I must say the quality of reproduction on this unit, knocks the Pioneer CT-F1250 we looked at earlier in the year into a cocked hat, but it is substantially younger!

It unidirectional, because the tape only ever travels in one direction, so no need for two capstans, two pinch rollers, and a complicated and compromised head which will play both sides of the cassette or a complicated mechanism to rotate the head.

Oh no, this uses a complicated mechanism to remove the cassette from the transport and turn it over!

A video is worth a thousand words....



All this machine wanted was a service, and a repair to the position sensor pot.

Arduino Astronomical Clock (and pond pump controller) - now with master clock update!

Well, the DS1307 clock module has a tendency to drift about a bit on my Pond pump controller. It can lose a few minutes each month. Irritating at best.

Now the GPS master clock as been created, it should be fairly easy to synchronise the DS1307 with the 433MHz data from the master clock.

The receiver hardware is connected to 5 volts, GND and it's data line is connected to pin 9 of the Arduino. The antenna is simply 17cm of stiff wire.

Once again, the wonderful Virtualwire library is used, and we simply call the receiver routine (remoteClockSet) in the main loop to see if any data has been received. If it has, update the DS1307, and recalculate the sun rise and set times.

There's a few more variables to declare to deal with the incoming time, and, to be honest the whole thing was written a while ago, and is now horribly un-weildy, and could do with a damn good tidy up and re-write, but it works.

No more difting clock!

Here's the code.


// Dawn & Dusk controller with frost protection. // (C) A.G.Doswell 2014 - 2016 // // Date and time functions using a DS1307 RTC connected via I2C and Wire lib // // Designed to control a relay connected to pin A3. Pin goes low during daylight hours and high during night. Relay uses active low, so is // "On" during the day. This is connected to the fountain pump in my garden. // // Time is set using a rotary encoder with integral push button. The Encoder is connected to interrupt pins D2 & D3 (and GND), // and the push button to pin analogue 0 (and GND) // The RTC is connections are: Analogue pin 4 to SDA. Connect analogue pin 5 to SCL. // A 2 x 16 LCD display is connected as follows (NOTE. This is NOT conventional, as interrupt pins are required for the encoder) // Arduino LCD // D4 DB7 // D5 DB6 // D6 DB5 // D7 DB4 // D12 RS // D13 E // // In this revision, there is a Dallas 18B20 Temperature sensor connected to pin 8, enabling frost protection. This is pulled up to +5volts via a 4.7K resistor. // // Use: Pressing and holding the button will enter the clock set mode (on release of the button). Clock is set using the rotary encoder. // The clock must be set to UTC. // Pressing and releasing the button quickly will display the current sun rise and sun set times. Pressing the button again will enter the mode select menu. // Modes are AUTO: On when the sun rises, off when it sets. // AUTO EXTEND : same as above but goes off 1 hour after sunet (nice for summer evenings!) // ON: Permanently ON // OFF: Permanently OFF (Who'd have guessed it?) // // Change the LATTITUDE and LONGITUDE constant to your location. // Use the address finder from http://www.hacktronics.com/Tutorials/arduino-1-wire-address-finder.html to find the address of your temperature sensor and enter it where required in DeviceAddress. // 28th Dec 2014 - Slowed the rate at which the temperature is requested down to once per minute. It has improved the clock display, and solved an issue whereby the temp sensor wasn't always ready to send data, and hung up. // 10th Jan 2015 - Altered the method of updating the temp to something simpler and more sensible! // 17th April 2015 - Stored Mode settings in EEPROM // 3rd Sept 2016 - Updated to run with 433MHz master clock updates. // // // Be sure to visit my website at http://andydoz.blogspot.com #include <Wire.h> #include "RTClib.h" // from https://github.com/adafruit/RTClib #include <LiquidCrystal.h> #include <Encoder.h> // from http://www.pjrc.com/teensy/td_libs_Encoder.html #include <TimeLord.h> // from http://swfltek.com/arduino/timelord.html. When adding it to your IDE, rename the file, removing the "-depreciated" #include <OneWire.h> // from http://playground.arduino.cc/Learning/OneWire #include <DallasTemperature.h> // from http://www.hacktronics.com/code/DallasTemperature.zip. When adding this to your IDE, ensure the .h and .cpp files are in the top directory of the library. #include <EEPROM.h> #define ONE_WIRE_BUS 8 // Data wire from temp sensor is plugged into pin 8 on the Arduino OneWire oneWire(ONE_WIRE_BUS); // Setup a oneWire instance to communicate with any OneWire devices DeviceAddress outsideThermometer = { 0x28, 0x1A, 0x1A, 0x3E, 0x06, 0x00, 0x00, 0xC7 }; // use the address finder from http://www.hacktronics.com/Tutorials/arduino-1-wire-address-finder.html to find the address of your device. RTC_DS1307 RTC; // Tells the RTC library that we're using a DS1307 RTC Encoder knob(2, 3); //encoder connected to pins 2 and 3 (and ground) LiquidCrystal lcd(12, 13, 7, 6, 5, 4); // I used an odd pin combination because I need pin 2 and 3 for the interrupts. //the variables provide the holding values for the set clock routine int setyeartemp; int setmonthtemp; int setdaytemp; int sethourstemp; int setminstemp; int setsecs = 0; int maxday; // maximum number of days in the given month int TimeMins = 0; // number of seconds since midnight int TimerMode = 2; //mode 0=Off 1=On 2=Auto int TimeOut = 10; int TimeOutCounter; // These variables are for the push button routine int buttonstate = 0; //flag to see if the button has been pressed, used internal on the subroutine only int pushlengthset = 3000; // value for a long push in mS int pushlength = pushlengthset; // set default pushlength int pushstart = 0;// sets default push value for the button going low int pushstop = 0;// sets the default value for when the button goes back high int knobval; // value for the rotation of the knob boolean buttonflag = false; // default value for the button flag float tempC; // Temperature // Over-Ride feature flag for Raminda Subhashana boolean OverRideFlag = false; const int TIMEZONE = 0; //UTC const float LATITUDE = 51.000, LONGITUDE = 2.000; // set YOUR position here int Sunrise, Sunset; //sunrise and sunset expressed as minute of day (0-1439) TimeLord myLord; // TimeLord Object, Global variable byte sunTime[] = {0, 0, 0, 1, 1, 13}; // 17 Oct 2013 int SunriseHour, SunriseMin, SunsetHour, SunsetMin; //Variables used to make a decent display of our sunset and sunrise time. DallasTemperature sensors(&oneWire); // Pass our oneWire reference to Dallas Temperature. #include <VirtualWire.h> // set up virtual wire for connection to 433MHZ Rx. #include <VirtualWire_Config.h> // set up integers for remote master clock int TX_ID = 1; int Hours; int Mins; int Secs; int Day; int Month; int Year; boolean Output; char buffer[5]; void setup () { //Serial.begin(57600); //start debug serial interface Wire.begin(); //start I2C interface RTC.begin(); //start RTC interface lcd.begin(16, 2); //Start LCD (defined as 16 x 2 characters) lcd.clear(); pinMode(A0, INPUT); //push button on encoder connected to A0 (and GND) digitalWrite(A0, HIGH); //Pull A0 high pinMode(A1, INPUT); // Over ride push button connected to A1 (and GND) digitalWrite(A1, HIGH); pinMode(A3, OUTPUT); //Relay connected to A3 digitalWrite (A3, HIGH); //sets relay off (default condition) sensors.begin(); sensors.setResolution(outsideThermometer, 12); // set the resolution to 12 bits (why not?!) //Checks to see if the RTC is runnning, and if not, sets the time to the time this sketch was compiled, also sets default mode to 2 and writes to EEPROM lcd.clear(); lcd.print("Waiting for RTC"); delay (3000);// wait a few seconds for the RTC to sort itself out. DateTime now = RTC.now(); if (! RTC.isrunning()) { RTC.adjust(DateTime(__DATE__, __TIME__)); EEPROM.update (0, 2); // set the auto mode as 2 (auto) for default } vw_set_tx_pin(10); // Even though it's not used, we'll define it so the default doesn't interfere with the LCD library. vw_set_rx_pin(9); // RX pin set to pin 9 vw_setup(1200); //sets virtualwire for a tx rate of 300 bits per second, nice and slow! vw_rx_start(); lcd.print("Dawn Dusk Pond"); lcd.setCursor(0, 1); lcd.print("Pump Controller"); delay (2000); lcd.clear(); lcd.print("Version 1.37"); lcd.setCursor(0, 1); lcd.print("(C) A.G.Doswell "); delay (5000); lcd.clear(); //Timelord initialisation myLord.TimeZone(TIMEZONE * 60); myLord.Position(LATITUDE, LONGITUDE); CalcSun (); TimerMode = EEPROM.read (0); // Read TimerMode from EEPROM delay (1000); } void printTemperature(DeviceAddress deviceAddress) { lcd.setCursor (9, 1); tempC = sensors.getTempC(deviceAddress); if (tempC == -127.00) { lcd.print("Err"); } else { lcd.print(tempC); lcd.print((char)0xDF); lcd.print("C "); } } void loop () { remoteClockSet (); DateTime now = RTC.now(); //get time from RTC //Display current time lcd.setCursor (0, 0); lcd.print(now.day(), DEC); lcd.print('/'); lcd.print(now.month()); lcd.print('/'); lcd.print(now.year(), DEC); lcd.print(" "); lcd.setCursor (0, 1); lcd.print(now.hour(), DEC); lcd.print(':'); if (now.minute() < 10) { lcd.print("0"); } lcd.print(now.minute(), DEC); lcd.print(':'); if (now.second() < 10) { lcd.print("0"); } lcd.print(now.second()); lcd.print(" "); //current time in minutes since midnight (used to check against sunrise/sunset easily) TimeMins = (now.hour() * 60) + now.minute(); //Get and display temp every minute if (now.second() == 7) { sensors.requestTemperatures(); // Request temperature delay (249); printTemperature(outsideThermometer); // display on lcd. } // Calculate sun times once a day at a minute past midnight if (TimeMins == 1) { lcd.clear(); CalcSun (); } // Reset Override flag if the sun is up! if (TimeMins == Sunrise) { OverRideFlag = false; } if (TimerMode == 2) { if (TimeMins >= Sunrise && TimeMins <= Sunset - 1 && tempC >= 2 && OverRideFlag == false) { //If it's after sunrise and before sunset, and it's not frozen, and our override isn't set, switch our relay on digitalWrite (A3, LOW); lcd.setCursor (13, 0); lcd.print ("On "); } else { //otherwise switch it off digitalWrite (A3, HIGH); lcd.setCursor (13, 0); lcd.print ("Off"); } } if (TimerMode == 3) { if (TimeMins >= Sunrise && TimeMins <= Sunset + 60 && tempC >= 2 && OverRideFlag == false) { //If it's after sunrise and before sunset + 1 hour, and it's not frozen, and our override isn't set, switch our relay on digitalWrite (A3, LOW); lcd.setCursor (13, 0); lcd.print ("On "); } else { //otherwise switch it off digitalWrite (A3, HIGH); lcd.setCursor (13, 0); lcd.print ("Off"); } } if (TimerMode == 0) { // Off digitalWrite (A3, HIGH); lcd.setCursor (13, 0); lcd.print ("Off"); } if (TimerMode == 1 && tempC >= 2) { // TimerMode is On, but it's not frozen digitalWrite (A3, LOW); lcd.setCursor (13, 0); lcd.print ("On "); } buttonstate = digitalRead(A1);// check to see if our override button is pressed, if it is, set the flag if (buttonstate == LOW ) { OverRideFlag = true; } pushlength = pushlengthset; pushlength = getpushlength (); delay (10); if (pushlength < pushlengthset) { lcd.clear (); ShortPush (); lcd.clear (); } //This runs the setclock routine if the knob is pushed for a long time if (pushlength > pushlengthset) { lcd.clear(); DateTime now = RTC.now(); setyeartemp = now.year(), DEC; setmonthtemp = now.month(), DEC; setdaytemp = now.day(), DEC; sethourstemp = now.hour(), DEC; setminstemp = now.minute(), DEC; setclock(); pushlength = pushlengthset; }; } //sets the clock void setclock () { setyear (); lcd.clear (); setmonth (); lcd.clear (); setday (); lcd.clear (); sethours (); lcd.clear (); setmins (); lcd.clear(); RTC.adjust(DateTime(setyeartemp, setmonthtemp, setdaytemp, sethourstemp, setminstemp, setsecs)); //set the DS1307 RTC CalcSun (); //refresh the sunrise and sunset times delay (1000); } // subroutine to return the length of the button push. int getpushlength () { buttonstate = digitalRead(A0); if (buttonstate == LOW && buttonflag == false) { pushstart = millis(); buttonflag = true; }; if (buttonstate == HIGH && buttonflag == true) { pushstop = millis (); pushlength = pushstop - pushstart; buttonflag = false; }; return pushlength; } // The following subroutines set the individual clock parameters int setyear () { lcd.setCursor (0, 0); lcd.print ("Set Year"); pushlength = pushlengthset; pushlength = getpushlength (); if (pushlength != pushlengthset) { return setyeartemp; } lcd.setCursor (0, 1); knob.write(0); delay (50); knobval = knob.read(); if (knobval < -1) { //bit of software de-bounce knobval = -1; } if (knobval > 1) { knobval = 1; } setyeartemp = setyeartemp + knobval; if (setyeartemp < 2014) { //Year can't be older than currently, it's not a time machine. setyeartemp = 2014; } lcd.print (setyeartemp); lcd.print(" "); setyear(); } int setmonth () { lcd.setCursor (0, 0); lcd.print ("Set Month"); pushlength = pushlengthset; pushlength = getpushlength (); if (pushlength != pushlengthset) { return setmonthtemp; } lcd.setCursor (0, 1); knob.write(0); delay (50); knobval = knob.read(); if (knobval < -1) { knobval = -1; } if (knobval > 1) { knobval = 1; } setmonthtemp = setmonthtemp + knobval; if (setmonthtemp < 1) {// month must be between 1 and 12 setmonthtemp = 1; } if (setmonthtemp > 12) { setmonthtemp = 12; } lcd.print (setmonthtemp); lcd.print(" "); setmonth(); } int setday () { if (setmonthtemp == 4 || setmonthtemp == 5 || setmonthtemp == 9 || setmonthtemp == 11) { //30 days hath September, April June and November maxday = 30; } else { maxday = 31; //... all the others have 31 } if (setmonthtemp == 2 && setyeartemp % 4 == 0) { //... Except February alone, and that has 28 days clear, and 29 in a leap year. maxday = 29; } if (setmonthtemp == 2 && setyeartemp % 4 != 0) { maxday = 28; } lcd.setCursor (0, 0); lcd.print ("Set Day"); pushlength = pushlengthset; pushlength = getpushlength (); if (pushlength != pushlengthset) { return setdaytemp; } lcd.setCursor (0, 1); knob.write(0); delay (50); knobval = knob.read(); if (knobval < -1) { knobval = -1; } if (knobval > 1) { knobval = 1; } setdaytemp = setdaytemp + knobval; if (setdaytemp < 1) { setdaytemp = 1; } if (setdaytemp > maxday) { setdaytemp = maxday; } lcd.print (setdaytemp); lcd.print(" "); setday(); } int sethours () { lcd.setCursor (0, 0); lcd.print ("Set Hours"); pushlength = pushlengthset; pushlength = getpushlength (); if (pushlength != pushlengthset) { return sethourstemp; } lcd.setCursor (0, 1); knob.write(0); delay (50); knobval = knob.read(); if (knobval < -1) { knobval = -1; } if (knobval > 1) { knobval = 1; } sethourstemp = sethourstemp + knobval; if (sethourstemp < 1) { sethourstemp = 1; } if (sethourstemp > 23) { sethourstemp = 23; } lcd.print (sethourstemp); lcd.print(" "); sethours(); } int setmins () { lcd.setCursor (0, 0); lcd.print ("Set Mins"); pushlength = pushlengthset; pushlength = getpushlength (); if (pushlength != pushlengthset) { return setminstemp; } lcd.setCursor (0, 1); knob.write(0); delay (50); knobval = knob.read(); if (knobval < -1) { knobval = -1; } if (knobval > 1) { knobval = 1; } setminstemp = setminstemp + knobval; if (setminstemp < 0) { setminstemp = 0; } if (setminstemp > 59) { setminstemp = 59; } lcd.print (setminstemp); lcd.print(" "); setmins(); } int setmode () { //Sets the mode of the timer. Auto, On or Off lcd.setCursor (0, 0); lcd.print ("Set Mode"); pushlength = pushlengthset; pushlength = getpushlength (); if (pushlength != pushlengthset) { EEPROM.update (0, TimerMode); //write the mode setting to EEPROM return TimerMode; } lcd.setCursor (0, 1); knob.write(0); delay (50); knobval = knob.read(); if (knobval < -1) { knobval = -1; } if (knobval > 1) { knobval = 1; } TimerMode = TimerMode + knobval; if (TimerMode < 0) { TimerMode = 0; } if (TimerMode > 3) { TimerMode = 3; } if (TimerMode == 0) { lcd.print("Off "); lcd.print(" "); } if (TimerMode == 1) { lcd.print("On "); lcd.print(" "); } if (TimerMode == 2) { lcd.print("Auto "); lcd.print(" "); } if (TimerMode == 3) { lcd.print("Auto Extend"); lcd.print(" "); } setmode (); } int CalcSun () { //Calculates the Sunrise and Sunset times DateTime now = RTC.now(); sunTime[3] = now.day(); // Give Timelord the current date sunTime[4] = now.month(); sunTime[5] = now.year(); myLord.SunRise(sunTime); // Computes Sun Rise. Sunrise = sunTime[2] * 60 + sunTime[1]; // Sunrise returned in minutes past midnight SunriseHour = sunTime[2]; SunriseMin = sunTime [1]; sunTime[3] = now.day(); // Uses the Time library to give Timelord the current date sunTime[4] = now.month(); sunTime[5] = now.year(); myLord.SunSet(sunTime); // Computes Sun Set. Sunset = sunTime[2] * 60 + sunTime[1]; // Sunset returned in minutes past midnight SunsetHour = sunTime[2]; SunsetMin = sunTime [1]; } void ShortPush () { //This displays the calculated sunrise and sunset times when the knob is pushed for a short time. for (long Counter = 0; Counter < 604 ; Counter ++) { //returns to the main loop if it's been run 604 times //(don't ask me why I've set 604,it seemed like a good number) lcd.setCursor (0, 0); lcd.print ("Sunrise "); lcd.print (SunriseHour); lcd.print (":"); if (SunriseMin < 10) { lcd.print("0"); } lcd.print (SunriseMin); lcd.setCursor (0, 1); lcd.print ("Sunset "); lcd.print (SunsetHour); lcd.print (":"); if (SunsetMin < 10) { lcd.print("0"); } lcd.print (SunsetMin); //If the knob is pushed again, enter the mode set menu pushlength = pushlengthset; pushlength = getpushlength (); if (pushlength != pushlengthset) { lcd.clear (); TimerMode = setmode (); } } } void remoteClockSet () { typedef struct rxRemoteData //Defines the received data, this is the same as the TX struct { int TX_ID; int Hours; int Mins; int Secs; int Day; int Month; int Year; }; struct rxRemoteData receivedData; uint8_t rcvdSize = sizeof(receivedData); if (vw_get_message((uint8_t *)&receivedData, &rcvdSize)) { if (receivedData.TX_ID == 1) { //Only if the TX_ID=1 do we process the data, and set the DS1307 int TX_ID = receivedData.TX_ID; int Hours = receivedData.Hours; int Mins = receivedData.Mins; int Secs = receivedData.Secs; int Day = receivedData.Day; int Month = receivedData.Month; int Year = receivedData.Year; RTC.adjust(DateTime(Year, Month, Day, Hours, Mins, Secs)); //set the DS1307 RTC CalcSun (); //refresh the sunrise and sunset times lcd.clear(); lcd.setCursor (0, 0); lcd.print ("Clock Updated"); delay (1000); lcd.clear(); } } }

Radio Rentals Model 218 radio, repairs and restoration.

My good friend Derek, has once again dropped off a challenge.

"Always wanted a set with a magic eye. This one's got no mains lead. Can you sort it?"

Why not...

It's a well designed set, with long, medium, shortwave and FM bands. The FM band only covers 88-101 MHz, as the police used the upper bit to 108 MHz as late as the 1980's in the UK.

It's tone control isn't the conventional variable control, but a three position switch. I can't really see why this was done. It involves a rotary switch, and 3 caps and resistors, rather than a pot, and one cap. Strange... maybe a switch and caps were cheaper than a pot !?


This set is a "purchase model", rental sets were marked as "Property of Radio Rentals." It dates from about 1956/57

Nice un-cluttered chassis...


















First off to disconnect the mains smoothing cap and hook it up to the MK87 "Dreadnaught" capacitor reformer, and leave each section to reform.

It doesn't take long, the capacitor isn't original, and is in fine shape.

 Odd "dog bone" resistor (yellow body, purple end, red spot!) ... more the sort of thing you'd find in a 30's or 40's receiver forms part of the power supply filter... can't be original, can it?









A few caps are evicted as a matter of course, and the switches and pots are cleaned up.











Initial results on LW and MW are good, then... POP ... silence.... A new EABC80 valve restores audio. Faults are not going to be easy to find, as I have no service information on this set.
Shortwave works OK too, not much selectivity, but that's only to be expected really. FM is awful. Almost nothing.... it's unstable. A quick sweep with the signal generator shows the thing to massively high in frequency. It's tuning about 140-150 MHz! A long period of head scratching, and tracing signals with the 'scope shows there's a 68pF capacitor open circuit. That brings the tuning back into range. It's not very sensitive, but things improve with a re-alignment of the IF and front-end. One problem remains. It's not good at handling modern broadcasts. The deviation is too wide, and bass is horribly distorted. Not much I can do about that really.

I spoke to Derek, and he's not too fussed about the FM, so it's time to crack on... Derek would like a line-level audio in though, for MP3 use, which is easy on this set, as it's transformer isolated, and has a "gram" input we can use...

A 3.5mm jack is added to the gram input, and shunted with a 10K resistor to earth, and 20K in series. Works really well, but gives us an electrical safety issue, as if a fault were to develop, the chassic could become "live", as would the MP3 player! Thankfully as the chassis is isolated by a transformer, we can add a 3-core mains lead. Testing this out gives no issues :)

Sound quality from it's large Goodmans speaker and EL84 amplifier really are very good indeed.

Magic eye is a little dim, but works well.. The "wings" close up as the signal strength increases to show when the set is correctly tuned.

So to box it all up, and final test. MP3 input works well.... but nothing on the radio ! Back out with the chassis again. Poking about around the wavechange switch, and there's a wire broken! Duly soldered back on, and still nothing! Traced the signal back to the EACB80 again.... (?) Starting to doubt my sanity, when I find another broken wire on the valve base from the IF transformer! I wonder if that was the original problem with the valve, and changing it just caused the broken wire to meet up again? Yep, replacing the valve with the original and it's still good.

Soak test for a few hours, and it seems fine ..!

"Just a wire off" .... sheesh!


Cleaned up nicely too.