Look at it.....
...Just look at it...
What a thing of beauty. A joy to behold.
I'm somewhat jealous. A quote from Hifi Engine "It has a genuine output of at least 40 watts continuous per channel into 8 ohms from 20Hz to 20,000Hz with no more than 0.05% total harmonic distortion." That's a very fine spec today, let alone 1978.
This one belongs to cheerful Martin, and has issues. It makes a noise like the tide going out when it's first switched on, some of the lamps have failed, the pots and switches are all scratchy, and Martin would like it re-capped. No mean feat.
Right, let's crack on...
... it's almost as good looking on the inside as it is on the outside... look at all the space (are you listening Aurex!)
Access is generally easy. We're going to need to remove the power amp board from the output transistors, and the volume control board to gain access to some of the caps thereon, but it's all very nice.
A quick look at the service manual and some nice Nichicon caps are on there way. (I would have gone with OE Nippon's, but the price!! I'm damned if I'll pay over £50+VAT each for some of them!)
The output transistor's heatsink is removed to facilitate change of capacitors, and the output transistors marked up, so they go back in the same order, and the old heatsink grease cleaned off and replaced with thermpath.
There's a considerable number of caps in this unit, so it takes some number of evenings to complete.
Martin mentioned he wanted the dial lamps replaced, as one had failed...
This necessitated removal of the front panel...
This necessitated removal of the front panel...
.. and the dial glass.
The white wire is disconnected from the power supply tag pin 10, and a 1N4007 diode and a 470uF capacitor are fitted to switch the supply to DC, so we can fit some appropriate LEDs easily...
... nice...
Bias is set for 45mA (after a minute or so's warm up), DC offset nulled out and the pots and switches cleaned.
And finally all buttoned up and tested.
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