PL82 v. PL83 - UK Vintage Radio Repair and Restoration Discussion Forum

Boom · 21st Mar 2009, 10:42 pm

Could anyone confirm for me that a PL82 is interchangeable with a PL83? I am looking at a circuit which gives a PL83 in the schematic and a PL82 in the base listings. The set actually has a duff PL83 in it.

Are they interchangeable or this is a mistake? More importantly are these rare ones? None listed on ebay. (I remember there was a PL84 too.)

TIA - Dave

AlanBeckett · 21st Mar 2009, 10:56 pm

Dave,
The Valve Museum says not. PL82 is audio, PL83 is video. The characteristics look quite a bit different. I'm afraid I have no direct experience of them.
Alan

Boom · 21st Mar 2009, 11:03 pm

Thanks Alan. Yes I had got that far but the PL83 is in the set as an audio output valve and the circuit (TV32) says this is correct however the base connections are given for the PL82.

Norman Raeburn · 21st Mar 2009, 11:49 pm

Hi dave, I have both PL82 and PL83 in my nos. Please pm me if you would like one and I will sort something out for you. Norman

AlanBeckett · 21st Mar 2009, 11:58 pm

Dave,
I'm afraid my valve books are in my cold dark shed at the moment. Also, I can't read the value of the cathode resistor on your circuit. However, doesn't that give some indication of what it should be?
Alan

Mr Moose · 22nd Mar 2009, 1:47 am

Hello,
They are not interchangeable. They have different base connections and characteristics. According to my information the PL82 is sound or frame amplifier and the PL83 is a video amplifier so one would think the valve should be a PL82 and not a PL83.
See:-http://www.mif.pg.gda.pl/homepages/f...030/p/PL82.pdf and http://www.mif.pg.gda.pl/homepages/f...030/p/PL83.pdf.
Yours, Richard

f.cooper · 22nd Mar 2009, 2:19 pm

Hi Dave,
Most of the Bush TVs from TV24 to TV43 appear to use a PL83 as the audio output valve. Various valves were used for video output from EF91,EF80 to PL83.
The PL83 is indeed listed by Mullard as a video output.
Looking at your diagram the base diagram shown as PL82 and comparing to the Mullard Valve data book it is NOT a PL82 but is a PL83.
Hope this helps to solve your problem.

Kindest Regards

Fred (G0BYU)

f.cooper · 22nd Mar 2009, 3:52 pm

Hi Dave,
I dont know the source of your circuit diagram or valve base diagram but after looking at the Trader sheets covering various Bush models TV24 to TV36, it appears only one is correct(sheet 1175). Trader sheets No 1003 and 1091 are completely wrong with their audio output valve base diagram - I do not have a clue what valve it could be for.
Trader sheet 1130 valve base diagram is almost a PL82 but is wrong on G2 and G3 connections. It also shows the cathode connected to both pins 1 &3. Mullard list pin 1 on a PL82 as an internal connection. Reading the Trader sheets text and valve listings they all refer to the PL83 as being used for the audio output valve. Note I was unable to find a reference to model TV32.
I hope the above is helpful and not confusing.

Kindest Regards

Fred (G0BYU)

Boom · 22nd Mar 2009, 4:07 pm

Thanks for input Fred. I have had another look and this seems to be the official Bush service sheet that I have here. (This is the front page of it) so any mistakes seem to have been passed down to the Trader from Bush themselves.

I have a PL83 on the way (immense thanks Norman) and will check it against the valve holder pins before I use it but am almost certain this is the correct valve for the SOP despite it being a video output valve.

I'm hoping there aren't any more errors as the TV32 is a pig to work on. In fact I can't work on the chassis 'live' due to the tube being fitted permanently to the cabinet. I.e. the tube and cabinet are totally seperated as the chassis is removed.

Having had a moan the cabinet has come up well and the EHT is now present (if a little low) so it's looking good.

Dave

f.cooper · 22nd Mar 2009, 4:52 pm

Hi Dave,
Sorry to be a pain but looking at the PL83 pin No's on your circuit diagram I could not read them properly. From the Mullard data book they are given as follows:-
Pin 1 G2,
pin 2 G1,
pin 3 K,
pin 4 h,
pin 5 h,
pin 6 G3,
pin 7 ANODE,
pin 8 s,
pin 9 IC,
Please check against your diagram.

Kindest Regards

Fred (G0BYU)

Boom · 22nd Mar 2009, 4:59 pm

Not a pain at all Fred. Thank you very much for your help. Your data ties in with what is quoted so if the PL82 is wired differently it has to be the valve number on the sheet that is wrong.

Dave

RogerWalker · 25th Mar 2009, 1:00 am

Definitely a PL83 - the PL82 has g3 and cathode joined internally whereas the PL83 has them on separate pins. The base diagram is wrongly worded "PL82".

The high slope of the PL83 probably saved Bush the cost of a triode audio stage?

Roger

21st Mar 2009, 10:42 pm	#1
Boom Retired Dormant Member Join Date: Jan 2007 Location: Westbury, Wiltshire, UK. Posts: 2,451	PL82 v. PL83 Could anyone confirm for me that a PL82 is interchangeable with a PL83? I am looking at a circuit which gives a PL83 in the schematic and a PL82 in the base listings. The set actually has a duff PL83 in it. Are they interchangeable or this is a mistake? More importantly are these rare ones? None listed on ebay. (I remember there was a PL84 too.) TIA - Dave

21st Mar 2009, 10:56 pm	#2
AlanBeckett Rest in Peace Join Date: Dec 2008 Location: Burton upon Trent, East Staffordshire, UK. Posts: 1,686	Re: Pl82 V Pl83 Dave, The Valve Museum says not. PL82 is audio, PL83 is video. The characteristics look quite a bit different. I'm afraid I have no direct experience of them. Alan

21st Mar 2009, 11:03 pm	#3
Boom Retired Dormant Member Join Date: Jan 2007 Location: Westbury, Wiltshire, UK. Posts: 2,451	Re: Pl82 V Pl83 Thanks Alan. Yes I had got that far but the PL83 is in the set as an audio output valve and the circuit (TV32) says this is correct however the base connections are given for the PL82. Attached Thumbnails

21st Mar 2009, 11:49 pm	#4
Norman Raeburn Heptode Join Date: Feb 2008 Location: Leven, Fife, Scotland Posts: 823	Re: Pl82 V Pl83 Hi dave, I have both PL82 and PL83 in my nos. Please pm me if you would like one and I will sort something out for you. Norman

21st Mar 2009, 11:58 pm	#5
AlanBeckett Rest in Peace Join Date: Dec 2008 Location: Burton upon Trent, East Staffordshire, UK. Posts: 1,686	Re: Pl82 V Pl83 Dave, I'm afraid my valve books are in my cold dark shed at the moment. Also, I can't read the value of the cathode resistor on your circuit. However, doesn't that give some indication of what it should be? Alan

22nd Mar 2009, 1:47 am	#6
Mr Moose Octode Join Date: Jul 2008 Location: Gloucestershire, UK. Posts: 1,043	Re: Pl82 V Pl83 Hello, They are not interchangeable. They have different base connections and characteristics. According to my information the PL82 is sound or frame amplifier and the PL83 is a video amplifier so one would think the valve should be a PL82 and not a PL83. See:-http://www.mif.pg.gda.pl/homepages/f...030/p/PL82.pdf and http://www.mif.pg.gda.pl/homepages/f...030/p/PL83.pdf. Yours, Richard Last edited by Mr Moose; 22nd Mar 2009 at 2:12 am.

22nd Mar 2009, 2:19 pm	#7
f.cooper Retired Dormant Member Join Date: Oct 2006 Location: Stoke-on-Trent, Staffordshire, UK. Posts: 128	Re: Pl82 V Pl83 Hi Dave, Most of the Bush TVs from TV24 to TV43 appear to use a PL83 as the audio output valve. Various valves were used for video output from EF91,EF80 to PL83. The PL83 is indeed listed by Mullard as a video output. Looking at your diagram the base diagram shown as PL82 and comparing to the Mullard Valve data book it is NOT a PL82 but is a PL83. Hope this helps to solve your problem. Kindest Regards Fred (G0BYU)

22nd Mar 2009, 3:52 pm	#8
f.cooper Retired Dormant Member Join Date: Oct 2006 Location: Stoke-on-Trent, Staffordshire, UK. Posts: 128	Re: Pl82 V Pl83 Hi Dave, I dont know the source of your circuit diagram or valve base diagram but after looking at the Trader sheets covering various Bush models TV24 to TV36, it appears only one is correct(sheet 1175). Trader sheets No 1003 and 1091 are completely wrong with their audio output valve base diagram - I do not have a clue what valve it could be for. Trader sheet 1130 valve base diagram is almost a PL82 but is wrong on G2 and G3 connections. It also shows the cathode connected to both pins 1 &3. Mullard list pin 1 on a PL82 as an internal connection. Reading the Trader sheets text and valve listings they all refer to the PL83 as being used for the audio output valve. Note I was unable to find a reference to model TV32. I hope the above is helpful and not confusing. Kindest Regards Fred (G0BYU)

22nd Mar 2009, 4:07 pm	#9
Boom Retired Dormant Member Join Date: Jan 2007 Location: Westbury, Wiltshire, UK. Posts: 2,451	Re: Pl82 V Pl83 Thanks for input Fred. I have had another look and this seems to be the official Bush service sheet that I have here. (This is the front page of it) so any mistakes seem to have been passed down to the Trader from Bush themselves. I have a PL83 on the way (immense thanks Norman) and will check it against the valve holder pins before I use it but am almost certain this is the correct valve for the SOP despite it being a video output valve. I'm hoping there aren't any more errors as the TV32 is a pig to work on. In fact I can't work on the chassis 'live' due to the tube being fitted permanently to the cabinet. I.e. the tube and cabinet are totally seperated as the chassis is removed. Having had a moan the cabinet has come up well and the EHT is now present (if a little low) so it's looking good. Dave Attached Thumbnails

22nd Mar 2009, 4:52 pm	#10
f.cooper Retired Dormant Member Join Date: Oct 2006 Location: Stoke-on-Trent, Staffordshire, UK. Posts: 128	Re: Pl82 V Pl83 Hi Dave, Sorry to be a pain but looking at the PL83 pin No's on your circuit diagram I could not read them properly. From the Mullard data book they are given as follows:- Pin 1 G2, pin 2 G1, pin 3 K, pin 4 h, pin 5 h, pin 6 G3, pin 7 ANODE, pin 8 s, pin 9 IC, Please check against your diagram. Kindest Regards Fred (G0BYU)

22nd Mar 2009, 4:59 pm	#11
Boom Retired Dormant Member Join Date: Jan 2007 Location: Westbury, Wiltshire, UK. Posts: 2,451	Re: Pl82 V Pl83 Not a pain at all Fred. Thank you very much for your help. Your data ties in with what is quoted so if the PL82 is wired differently it has to be the valve number on the sheet that is wrong. Dave

25th Mar 2009, 1:00 am	#12
RogerWalker Hexode Join Date: Sep 2005 Location: Powys, Mid-Wales, UK. Posts: 289	Re: Pl82 V Pl83 Definitely a PL83 - the PL82 has g3 and cathode joined internally whereas the PL83 has them on separate pins. The base diagram is wrongly worded "PL82". The high slope of the PL83 probably saved Bush the cost of a triode audio stage? Roger