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Success Stories If you have successfully repaired or restored a piece of equipment, why not write up what you did and post details here. Particularly if it was interesting, unusual or challenging. PLEASE DO NOT POST REQUESTS FOR HELP HERE!

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Old 9th Feb 2020, 10:25 pm   #1
AD360 Rob
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Default Bush SRP41 Record Player repair

Evening all, thought I'd like to share with you the story behind this Bush and the merry dance it led me.

It all started when I won it at a Radiophile auction for literally a few quid. It was filthy dirty and towards the end of the sale. It had also been stored in less than ideal conditions as there is some slight corrosion under the black paint on the deck. Now, transistorized record players aren't really my thing, I much prefer vavled ones but I thought " as it's a Bush, might be better quality than most".
It sat on the "to do" pile for a month or so and after clearing a couple of other jobs that had been hanging around I got it on the bench, checked a few things like turntable spins freely, arm moves smoothly etc, plugged it in and was rewarded by an apparently working player. The BSR UA15 was working but a little sluggish so that was the first port of call, cleaning off old grease and re-lubricating, the deck now performs beautifully. Say what you like about these all metal BSR decks, they do seem to be easy to get going again and work well when they are.
As the electronics seemed to be working fine apart from a little noise from the controls I gave the unit a good clean with car upholstery cleaner and luke warm water which brought it up a treat.
Anyway, I was giving it a thorough workout (these players go LOUD) when suddenly the sound cut out totally, not even a residual hum. At first I thought the internal fuse might have blown but this being a Mk 1A, it uses the later psu A577 which doesn't have a fuse. I did some measurements and the PSU was indeed working giving me 27.5V at pin 1 of the Amp PCB.

Further measurement revealed most transistor voltages were more or less spot on but some of the electrolytics looked a bit the worse for wear so these were duly removed, tested for leakage, value and esr and replaced as they were all giving odd readings (some low in value, others high ESR and one quite leaky) checking voltages after replacement revealed all ok apart from TR3 which was just about cut off, indeed the scope revealed perfect audio on the base but nothing (apart from DC) on the collector. I whipped the transistor out and tested it, it was ok. . . then I remembered that these AC128 types can suffer tin whiskers, a check between electrodes and case revealed a dead short between collector and case. A new AC128 was fitted, power applied and. . . still no sound unledss volume was at full when distorted peaks came through. Voltages were still a bit off on this transistor so a deeper look was needed. Whilst checking the resistors around the transistor, one decided to fall apart when I touched the probe on it (R8, 6.8K "dog bone type) this was replaced and audio was restored for a few seconds but this time it faded out.
A LOT of head scratching later and I eventually found that it was my fault. I had fitted all the PCB mounted electrolytics the wrong way round. I had become confused by the type originally fitted and had assumed that the end with the rubber seal on was the positive pole. Not so on these all red plastic bodied types, the positive pole is the one that comes out of the solid plastic body ! re-orientating the capacitors the correct way around finally restored perfect audio. Definately one for my little book of useful info.

Rob
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Last edited by AD360 Rob; 9th Feb 2020 at 10:30 pm.
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Old 11th Feb 2020, 1:03 am   #2
ben
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Default Re: Bush SRP41 Record Player repair

Great write up and a fantastic outcome. With regard to caps...we've all been there I am sure. In my case, the most recent time was only last week when I somehow fitted a small electrolytic back to front in a tape recorder and was rewarded with 'orrible white smoke!

I have a soft spot for these and in fact I used to have an SRP41, still have the manual but the player was I think discarded while I was away studying years ago. I now have an SRP31D with UA16 deck which is of course almost the same as the UA15SS the SRP41 uses.

If your Sonotone 8TA cart is still okay, then congratulations!
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Old 11th Feb 2020, 7:50 am   #3
AD360 Rob
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Default Re: Bush SRP41 Record Player repair

Morning Ben and thanks for your kind words, Yes, the original Sonotone 8TA cartridge is working fine, I must say that cartridge is one of the nicest sounding ceramics I have heard, detailed and smooth sounding. I spent a happy evening last night listening to some of my old Lps on it. I also have an SRP31 Think it's a D but not sure till I get it on the bench. That might be next actually.

Rob
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Old 11th Feb 2020, 2:19 pm   #4
Edward Huggins
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Default Re: Bush SRP41 Record Player repair

A lot of these are sold on-line and are usually described as having "twin speakers"!

I politely advised one seller so as to avoid him having any issues with the Buyer - and was immediately rewarded with abuse.....
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Old 11th Feb 2020, 3:09 pm   #5
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Default Re: Bush SRP41 Record Player repair

And you were surprised?
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Old 18th Feb 2020, 9:20 pm   #6
John10b
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Default Re: Bush SRP41 Record Player repair

I thought the SRP41 was very good looking record player, I’m sorry I sold mine.
I did have the idea of making it into a stereo rp, fitting new amp, twin speakers and with new cartridge. I mentioned this on the forum and was “shot down” and told it was a ...... idea.
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