Those Pesky Pye BBs! - UK Vintage Radio Repair and Restoration Discussion Forum

Edward Huggins · 24th May 2017, 5:10 pm

There was nothing straightforward about any of 'em as recent Posts have proven......
From the first 1954 Pentode, and then later UL versions, with their melting transformers to the multiple feedback BBA with those delicate PCL83s.
Even the rare Pye "Super Black Box" had problems wide that wide-dispersion electrostatic tweeter and the most complex of all the BB autochangers.
Then came the 1004 (US Columbia clone) with its all-germanium amp needing close tolerance components and accurate voltage ratings.
The piece de resistance was surely the 1005 Pye/CBS Achoic which when it worked was superb - but even when relatively new ones failed, many were shipped back to Cambridge where the "few who knew" were in A&E.
There are a lot still out there and they will be cropping up for many years to come, keeping Forum Members challenged with their quirkyness.....

unitaudio · 25th May 2017, 4:12 am

Hello Edward. I had a 1005 Achoic in the 1980's and keeping it working was an ongoing task. In fairness, by the time it was 20 years old it had lived a hard life and must have been well past it's best by the time it fell into my hands. It sadly ended up as a parts donor, I'd given it several of my best shots but they evidently weren't enough.

Regards,
Paul

Radio Wrangler · 25th May 2017, 7:07 am

But there were amplifier designs of that period which worked splendidly and were reliable. The Mullard designs, the Leaks. Pye built in a lot of complexity but really didn't do the job properly. There was always that last attempt to save a few pennies here and there which doomed the thing. A pair of EL84s, a couple of ECC83s, some slightly larger transformers... would it have ended the world?

David

wd40addict · 25th May 2017, 1:13 pm

I've always wondered if Pye just got a good deal from Mullard for some of the less popular types (EL41, PCL83) and then built amplifiers around them.

US Heathkit were guilty of using some weird types and I wonder if they picked up large batches of ex-government at a bargain price.

Nuvistor · 25th May 2017, 3:27 pm

I fixed the odd one but that's going on 50 years ago. I don't remember them being difficult but I could get original spares and of course I could have been very lucky.
Design life would have been maximum 10 years, not sure if it's worth berating the designers after all this time. The majority BB's would have done what they were deigned for.
Appreciate the Leaks etc are still viable but that would not have been a design consideration even for them.
If a piece of electronics is 50 years old and it can be made to work again with whatever spares are available I reckon that's a win.
Frank
Edit. Perhaps I need a tin hat after this post

David G4EBT · 25th May 2017, 5:16 pm

Quote:

Originally Posted by Edward Huggins

There was nothing straightforward about any of 'em as recent Posts have proven......There are a lot still out there and they will be cropping up for many years to come, keeping Forum Members challenged with their quirkyness.....

?Or for those with a low frustration threshold, landfill perhaps?!!

Edward Huggins · 25th May 2017, 5:40 pm

Quote:

Originally Posted by wd40addict

I've always wondered if Pye just got a good deal from Mullard for some of the less popular types (EL41, PCL83) and then built amplifiers around them.

Not really, the PCL83s came from vast quantities of 405 line TV pre-ordered stocks!! Pye were building a lot of Tellies in those days, although many would end up under a bulldozer at a certain airfield a few years later.....the PCL83s in-situ!

Nickthedentist · 25th May 2017, 7:58 pm

My first record player was a BBH MkI, bought for me secondhand by my parents from friends who were finally going stereo, when I was about 3 years old and the machine was already nearlly 25 years old.

It got a real hammering, playing all manner of LPs, singles and 78s all day long, its amp often being inadvertantly left on all night too. It was retired about 10 years later, to be dragged out occasionally to play 78s. The only "fault" was the speeds going awry because of the motor pulley slipping down the spindle, which dad would correct for me every few years.

It continued to "work" with no servicing whatsoever until I gave it a once-over about 10 years ago, when I discovered that one half of the OP transformer had gone O/C. Ed Dinning re-wound it for me, I replaced all the Hunts caps, stripped the UA60 and reglued the speakers' supsension, and now it's still going strong.

Not bad for something that's over 60 years old now.

24th May 2017, 5:10 pm	#1
Edward Huggins Dekatron Join Date: Sep 2015 Location: Southwold, Suffolk, UK. Posts: 8,324	Those Pesky Pye BBs! There was nothing straightforward about any of 'em as recent Posts have proven...... From the first 1954 Pentode, and then later UL versions, with their melting transformers to the multiple feedback BBA with those delicate PCL83s. Even the rare Pye "Super Black Box" had problems wide that wide-dispersion electrostatic tweeter and the most complex of all the BB autochangers. Then came the 1004 (US Columbia clone) with its all-germanium amp needing close tolerance components and accurate voltage ratings. The piece de resistance was surely the 1005 Pye/CBS Achoic which when it worked was superb - but even when relatively new ones failed, many were shipped back to Cambridge where the "few who knew" were in A&E. There are a lot still out there and they will be cropping up for many years to come, keeping Forum Members challenged with their quirkyness..... __________________ Edward.

25th May 2017, 4:12 am	#2
unitaudio Heptode Join Date: Sep 2013 Location: Manchester, UK. Posts: 862	Re: Those Pesky Pye BBs! Hello Edward. I had a 1005 Achoic in the 1980's and keeping it working was an ongoing task. In fairness, by the time it was 20 years old it had lived a hard life and must have been well past it's best by the time it fell into my hands. It sadly ended up as a parts donor, I'd given it several of my best shots but they evidently weren't enough. Regards, Paul __________________ ...No, it's not supposed to pick up the World Service, it's not a radio!

25th May 2017, 7:07 am	#3
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,857	Re: Those Pesky Pye BBs! But there were amplifier designs of that period which worked splendidly and were reliable. The Mullard designs, the Leaks. Pye built in a lot of complexity but really didn't do the job properly. There was always that last attempt to save a few pennies here and there which doomed the thing. A pair of EL84s, a couple of ECC83s, some slightly larger transformers... would it have ended the world? David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

25th May 2017, 1:13 pm	#4
wd40addict Octode Join Date: May 2009 Location: Stevenage, Herts. UK. Posts: 1,518	Re: Those Pesky Pye BBs! I've always wondered if Pye just got a good deal from Mullard for some of the less popular types (EL41, PCL83) and then built amplifiers around them. US Heathkit were guilty of using some weird types and I wonder if they picked up large batches of ex-government at a bargain price.

25th May 2017, 3:27 pm	#5
Nuvistor Dekatron Join Date: Aug 2013 Location: Wigan, Greater Manchester, UK. Posts: 9,431	Re: Those Pesky Pye BBs! I fixed the odd one but that's going on 50 years ago. I don't remember them being difficult but I could get original spares and of course I could have been very lucky. Design life would have been maximum 10 years, not sure if it's worth berating the designers after all this time. The majority BB's would have done what they were deigned for. Appreciate the Leaks etc are still viable but that would not have been a design consideration even for them. If a piece of electronics is 50 years old and it can be made to work again with whatever spares are available I reckon that's a win. Frank Edit. Perhaps I need a tin hat after this post

25th May 2017, 7:58 pm	#8
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,837	Re: Those Pesky Pye BBs! My first record player was a BBH MkI, bought for me secondhand by my parents from friends who were finally going stereo, when I was about 3 years old and the machine was already nearlly 25 years old. It got a real hammering, playing all manner of LPs, singles and 78s all day long, its amp often being inadvertantly left on all night too. It was retired about 10 years later, to be dragged out occasionally to play 78s. The only "fault" was the speeds going awry because of the motor pulley slipping down the spindle, which dad would correct for me every few years. It continued to "work" with no servicing whatsoever until I gave it a once-over about 10 years ago, when I discovered that one half of the OP transformer had gone O/C. Ed Dinning re-wound it for me, I replaced all the Hunts caps, stripped the UA60 and reglued the speakers' supsension, and now it's still going strong. Not bad for something that's over 60 years old now.