Classic Mini 1275GT gets an interior and earns it's stripes!

Still been working on the Mini when I can... it's taking too long!

Recently, it was time to fit the interior back in. I fitted it, then took it back out again. It's grubby, and horrible, nothing like the original one (it was swapped out sometime in the 90's for a British Open interior).

I looked around for a suitable replacement, and finally stumbled on a company via facebook called Autostitch, who gave me some ideas and a very favourable quote.

The kit arrived after a short wait, and I set about fitting it to the existing seats. I chose not to replace the foam in the seats, as it still appeared to be in good order.

First off I started on the rear seat base. It was easy enough to remove the old upholstery, as it's just held on with some staples...










The foam's in good condition...

The new upholstery is sized up...












.. and once I've got it round the right way (!), stapled in the middle either side, putting the vinyl under a bit of tension ..

.. and stapled round the edge, moving out from the middle, avoiding any uneven tension which may cause it to wrinkle up...










Now, I've never done anything like this before, and it's all gone very well :)

On to the back.












This is of different construction. It's a wire frame, with very scant foam padding! The upholstery is held in place with a lot of small clips. I took a good few photos of the position of the clips, just in case, but I need not have worried...

One note about the clips, the come in two different sizes, a wide (pictured here) which is intended to "grab" two thicknesses of upholstery, where they overlap, and a narrower type, intended to grab one thickness.. 

The new vinyl is again sized up, and fits really easily...

Not bad at all :)

On with the fronts...

Here's a tip, remove the head-rests before un-bolting the seats from the car!

These are the slightly later type of seats, with the latching bar, and the reclining mechanism (oh the luxury!)

First thing is to turn the seat upside down..

.. and remove the rear part where it's folded around the seat base to reveal 30+ years of crap... ugh!

You'll find several little clips, not dissimilar to the ones used to hold the back seat cover to the frame.

Remove the recliner handle (just one philips screw) and the little silver rivet from the other side.

Slide the rear cover from the seat.. Again, the foam is a little discoloured, but hasn't started to degrade.

Remove these two cardboard things from the rear cover, you'll need to put those back in to the replacement cover.

Undo the clips from abound the base of the seat..

Remove the latch level knob (it just unscrews)

Squeeze the sides of the latch bar grommet from the inside, and it should pop out...

And remove the upholstery and foam.

It appears my seat frame was made in the motherland, by Llanelli radiators!!

















Now's the time to paint up any rusty bits on the seat frame.

Installing the covers is easy, just take your time, stretching the vinyl over the seat frame and foam, and knocking the clips back on with a small hammer.

Door cards are a direct fit, although tight in the top slot on the door, which is no bad thing!

You'll need to make some small holes in the vinyl (I used a hot soldering iron) to locate the screws for the door handle.












Finally looking good...

Meanwhile, Lee gave me a bell ...

"My fishing bite alarm has stopped working.. can you have a look?"

... yeah, why not?

The receiver had a nasty case of corrosion, so after a good clean up in the ultrasonic bath, and some microsurgery around the PLL, it was sorted :)


Now Lee is a renowned car  body expert, as thanks for the fishing bite alarm repair, he very kindly offered to fit my side stripes for me, a job which I've attempted to do once, and cocked up (in my defence, more to do with the age of the stickers , which were genuine Leyland ones, and they had hardened over the years and stuck to the backing.) These are aftermarket heritage decals, be very careful where you get them from, as I had some from a reputable supplier, which I returned as the stripes top and bottom were too wide, and the font very wrong...


He didn't even mind about the rather cramped conditions, or the fact it was raining at the time..

It's finally earned it's stripes.










I've also sorted the radio cassette (see here for restoration), now with added bluetooth FM modulator, and accompanying USB and DC sockets...

... and mounted the Multi-function display where the ashtray once lived.

The bezel was 3D printed by my friend Pyers.

(The 3D print files are now available ...
https://andydoz.blogspot.com/2020/03/classic-mini-lcd-surround.html)

In other news....

The engine and gearbox is done and ready to go...

Including this rather nice lightened flywheel, and "orange" Borg & beck clutch, which has just returned from being balanced by the lovely people at MED.














Soon perhaps?

Automated APT weather satellite reception (Part 1)

Well, things are busy as ever at Chez Doz.

Keep a watchful eye out for forthcoming projects soon, including part 2 of this, which is going to show a completely self contained 137MHz APT Weather satellite receiver and antenna based around the raspberry Pi. It'll be a while as I'm busy building a self contained web based transmitter for the hospital radio at the moment, and the firmware is giving me a head ache!

Anyway, in the meantime, I've set up the wrong receiver (an Icom IC-R2), with the wrong antenna (a discone) in Evesham, and you can view the (unremarkable) reception on this website ...

http://andydoz.epizy.com/

Click on Evesham. The Cheltenham page isn't supported as yet.

Stay safe and stay tuned!

***STOP PRESS*** 19/06/2020

It appears epizy.com don't allow "automated uploads" , and have closed my account. I'll make a new post when I find another solution.

https://andydoz.swdg.co.uk/

Hitachi HT-L33 turntable repairs.

I was given this by a kindly benefactor...

It's a Hitachi L33 turntable from about 1982.

"It plays too fast, I've tried to adjust the speed, 33 is just about OK, but 45 is wrong"

Great, this will do as a gift to my mate Alan, who's been on the lookout for a sensible small turntable for a while.

I check both speeds, which seem to be far too fast, and varying badly.

Here's the speed circuit from the manual...

The motor PWB (printed wiring board, don't ya know!) is housed inside the motor. It's a brushed DC motor, controlled by a small regulator on the board. Normally the speed is adjustable via a small hole, operating a pot inside the motor. In this case, that connection is made available outside the motor, via the orange wire.

The speed is first set to 33 RPM, whereby the FET Q01 is switched on by the micro processor, and is effectively short circuiting R42 (the 45RPM control) and R41. Once R40 (33 RPM control) is set, you can then adjust 45. Doing it the other way round won't work, as 33 RPM will also adjust 45! The whole motor and speed arrangement is fed by a regulated 9.9V supply from Q11. Q10 is there to rapidly bring the motor up to speed, under control from the micro.

OK, the pots are already set to minimum speed. Damn... why so fast ?

Incidentally, be careful to secure the platter in place with some tape (or remove it) before turning this upside down. If you don't the platter will hit the stylus and probably ruin your day.

Ah! The belt has ridden up the pulley! Effectively changing the gearing..

The belt is moved into the correct position and re-tried. It's now running too slow, and followed a few seconds later by too fast...

The belt had ridden back up the pulley.

Removing the motor shows that the motor mount hadn't been installed correctly.

Now it's running steady in the correct place, but too slowly.

Using the cueing button, just moving the arm to the left starts the motor at 33, whilst we still have the lid up...

Adjust for 33.33333 RPM!

Seems reasonable !
















and then press the speed select switch, and adjust for 45 RPM.

Close enough.















A quick look at the stylus under a microscope shows it's in good health, so off to Alan it goes!

An easy fix, and a stylish linear tracking deck. All Alan needs now is a phono pre-amp!

Another saved from landfill!

Strathclyde STD 305D power supply.

I'd popped down to Brighton for a few days, to see my good friend Edouard.

He's got a very nice looking Strathclyde STD305D ..

"Got it on eBay, doesn't work, and appears to have bits missing.. Fancy a look?"

Yeah, why not...

A super turntable, which uses a proper DC brushed motor, a tacho and proper servo control...

Those speed adjusting sliders you see there, are actually tiny thumbwheels, which move up and down the track, allowing precision adjustment of the speed. Nice!

There's a digital display (presumably) for speed, and soft touch controls.

Here's the control PCB...

And here's the motor, and what remains of the power supply....

Some bugger's had the transformer!

It looks like they had a hum pickup problem (or galloping paranoia) and moved it outboard. Edouard didn't have it...




Thankfully someone had carefully marked all the voltages on the board, the original transformer had a good few windings on it...

It was (allegedly) wound 18.5-9-1.5-0-1.5.-9-18.5 

This is not going to be so easy , and is likely going to need multiple transformers, as I did to get the Tascam Portastudio 488 going.

I quickly sketch out the supply schematic, and realise something odd's going on with the 1.5 volt side of things... it appears to supply AC off to the control board... The other rails are simply rectified, smoothed and regulated.

Remembering the Tascam again, I trace the AC from the 1.5-01.5 across the control board, and it supplies the filament for the Vacuum florescent display! Ah!

A couple of suitable transformers are ordered for the 18 and 9V supplies, and cobbled up in the usual lethal manner to prove the point. To supply the 1.5-0-1.5 , a 20-0-20 transformer has it's primary supplied by the 9V transformer.

The point isn't proved.. it's pulling the best part of 100W from the mains! 18V transformer has got damn warm.

Tracing the circuit for the 18V through shows whomever measured it in the first place got it very wrong. It's not 18-0-18 .. it's just 18 - 0 ... connected across the two 18V connections. It's not 0 at all.. it's a bridge rectifier circuit. Checking the 9V shows that's a bridge too, not a centre-tapped full-wave circuit as the note left on the board suggests. The other very odd thing is the four fuseholders on the board. They fuse each half of the bridge ... why?? The 1.5V is, however centre tapped.

Once this is sorted, consumption falls to a sensible 14W. Nothing gets warm!

Here's the diagram.

T1 and T2 supply the 9 & 18V supplies.
T3 is a 6VA 0-20 0-20 transformer, the primary of which is wired for 120V operation, but supplied from the 18V supply. It's output provides the 1.5-0.1.5 output for the filaments.

The output is taken to a 9-way D.

Excellent. Well, nearly. The touch selector isn't working. No matter what speed is selected. It's always 33 RPM. Disassembly of the front panel finds a 7400 which is rather warm, this is replaced and all is well :)







 Touch sensors work perfectly, and the speed is stable


















Now to tidy up the rat's nest supply!















And done... :)

To sum up, a simple job which took far too long due to me trusting the incorrect work of two people... 1. The person who wrote out the label... 2. The person who laid out the power supply PCB incorrectly.

Nevermind...





*** STOP PRESS***

If you've landed here because you're looking for a solution to a faulty display ... look here 

The comprehensive Linn Valhalla repair guide.

John rang...

"Got a few Valhalla power supplies here that are defeating me, can you take a look?"

Yeah, why not.

Now these were the stalwart LP12 PSU once they'd decided that a crystal controlled supply was a good idea. Don't forget boys and girls; Linn ownership is all about upgrades, right?


Be aware all of this power supply is not isolated from mains. Use an isolation transformer during repair and fault finding. Make sure not to inadvertently earth the GND with your scope. You're no longer isolated if you do!
See the red bit in the disclaimer.

It a simple circuit. A 3.768MHz crystal is divided down to get a 50Hz square wave by IC3 (a 4060), and IC5 (4013) . This is switched through some control logic (IC4, another 4013), via the one preset on the board , to a square-wave to sine wave converter formed by IC2 (LM3902), which also provides some gain to drive Q1 & Q2 which drives the output stage formed by Q's 3 & 4. As the output is single ended it's DC component is removed by C18, and supplied to one phase of the motor. A phase shift capacitor is used to drive the other phase.

Most faults can be cleared by changing ALL the electrolytic capacitors, there are 7 in total.

C1,2 and 8 are 47uF 250V axial parts.
C3 is a 220uF 10V axial.
C8 & C15 is a 22uF 50V radial.
C14 is a 1uF 50V radial.

Use quality 105 degree parts. John had already done the caps ...

If that doesn't put it right, check for the presence of 320VDC on the positive end of C1 to GND. This is the HT supply. If that's missing, check the mains fuse (doh!). I've seen the bridge rectifier (BR1) fail a few times. If it's one of those odd looking square or rectangle things a Vishay W10G-E4/51 is an ideal replacement. R1 (47R) is also a frequent flyer!
A short circuit output stage will also cause violent fuse blowing!

Check for the presence of about 9VDC across C3. This is the LT supply. If it's missing, check R2 and R3, both 15K/5W for high or open. Change for a 7W part. They run damn hot. I always try and mount them a little off the board to allow for a bit of airflow. Some older boards can be quite scorched! IC1 can fail giving intermittent or no 9V. It can be replaced by MC3386/MC3346/LM3045/LM3046/LM3144 or an ECG912 (I don't think I've ever even seen one of those!) Z1, a 7.6V 0.25W zener diode, can also go short, open or drift. If you get an unstable or intermittent 9V, change this before IC1. If the 9V is being loaded down by a fault on elsewhere, generally an offending IC, which will reveal itself by getting damn hot! If you're really unlucky (and it has happened) I've seen instances where all the ICs have failed. Other symptoms of a poor 9V rail are inability to set the 85V up, and dim/no LED, even if the supply appears to be working.


Now the supplies are present, check for a 200Hz square wave output on pin 3 of IC3, if that's missing, the crystal or the IC itself may have thrown in the towel.










Square waves present? Good ... Now push the start button. 200Hz Square waves should be present on pin 12 of IC5. If they aren't there suspect the switch itself, or IC 4 or 5.










OK, you should now have a reduced amplitude 50Hz square wave on the end of R14 nearest the pot (there's a 4V DC offset here). If you haven't the pot has gone open (caught me out once!).










Scope the waveform on pin 14 of IC2, it should be a nice healthy 50Hz sine wave. If it's not, replace IC2.











Measure the voltage on pin 10 of IC2. Should be 1.9VDC with respect to GND. If it's not, check the value of R32 (560K). It often goes high, upsetting the bias of the output stage.

Still not working? Check Q1 (BC327, tends to fail open), Q2 (very rarely fails), Q3 and Q4 (either 2SC2501 or BUX84). The BUX84 has a nasty habit of going low gain, and causing issues. Measure it's HFe, should be over 20.

D2 very occasionally fails open, causing the motor to hum or not start. C19 causes the same issue.

The motor is often at fault on high mileage units! Check by substitution. Get a motor from Rega, it's the same and less money! Unlike the Axis, the motor will happily run all day without belt or platter.

Be careful when changing parts as the print quality varies from reasonable to awful. None as bad as the Axis!  There are many slight revisions to the boards, many have slightly different markings, a transistor can be marked Q,VT or TR. IC's U or IC.

Finally adjust the pot for 85V on the negative end of C18, or between the grey and red wires on the motor.

Now sit back, and enjoy some music.

LG GR-L206CPQA fridge freezer repair.

I'm sat in the lounge watching the news....

Ding-dong. Ding-dong. Ding-dong. Ding-dong.

Funny... that's the noise our fridge makes when someone pushes a button on the front panel.

I walk into the kitchen... it stops...

It appears our fridge is possessed (possibly by the curry I stuck in it's freezer compartment last night)

Ding-dong. Nope, it's altering it's fridge temperature settings on it's own...

I'll take a look before organising a priest....

It's an LG of some vintage. It wasn't new when we got it... ah, found the logo under some of the fridge magnets...

Let's get the front panel off... Grasp the panel and gently pull it off...












Unplug the PCB and retire to the workshop with the front...












The PCB is secured to the front panel with two philips screws...










... and removed shows the three tactile switches. One for freezer temp, one for fridge temp, and one switches the ice making thing into different modes.

Sure enough the fridge temp switch reads leaky, at about 40 kilohms. Checking the others show them to be better, but still a bit leaky at ~200 kilohms.




Sadly, I'm out of stock of suitable switches, so I order some. In the meantime, I give the switches a good dose of switch cleaner, which seems to fix it (at least temporarily, whilst the replacement switches arrive)

Another (and probably damned expensive thing to replace) saved from consignment to an expensive de-gassing and recycling scheme, if not landfill.

Lindos LA102 test set repair.

Morning ... coffee ... switch the power to the bench on and contemplate the day's work..

... hang on, the ever-faithful Lindos LA102 Audio measuring test set fails to start up.

It's dead, nothing. Thankfully I have a spare.

A cursory check round shows the mains transformer to have failed open circuit...

Fair enough, it's been in there since the 80's...











A suitable replacement looks like RS 121-3839, and is duly ordered...









Now it physically fits in the hole, we'll need to switch the phases on one of the primary windings, and one of the secondaries.. The original transformer is wired 0-120 0-120, and 0-6 0-6, the replacement is 0-115 115-0 and 0-6 6-0.  I'm not worried about the 5V difference in the primary.

So let's deal with the secondary first ... This is a picture of beneath the transformer.

Cut the tracks as shown.


















And connect two insulated wires to cross the tracks over...

You can now fit the transformer.

Next to deal with the primary. Cut the original link, and carefully remove the trace completely. Note I'm working on a 240V UK unit here... if you're in that funny bit of the world where you use 110 or 115V, you'll need to work it out so both primaries are in parallel.















Then add a link wire in to couple put the windings in series, and in the correct phase...

















... and reconnect the mains supply.


















Switching on, and it's clear something is not right. The transformer is humming and getting warm rapidly!  (It's never easy, is it??)

Turns out the bridge rectifier is short circuit as well... poor thing is cracked too...

It's replaced, and now the unit powers up, but it's still not right, as the power supply is still under some considerable  load...













... and the final piece of the puzzle is the ancient nicad battery is almost short circuit. I disconnect it, as I haven't ever needed it.
















Now, let's get on with some work!