Pye 48A from the grave to life - UK Vintage Radio Repair and Restoration Discussion Forum

jonnybear · 12th May 2020, 12:17 pm

Living in lockdown I dug out this old 48a I was given as a wreck while having a clear out, no valves, valve bases broken, smoothing cap exploded, no dropper or dial cabinet covered in paint, was just going to scrap it when I thought rather than sitting around I will make it a little project.
Replacing valve bases with B9A using ECH81,(CCH35) EF85,(EF39) EB91, and EL90 (CBL31)Russian 9 pin
rewired recapped fitted mains transformer for heaters and whalla one working radio,the loudspeaker was OK, now to find a dial a back and strip the cabinet.
John

rojosuiza · 12th May 2020, 1:43 pm

Nice title, good work.

vinrads · 12th May 2020, 3:58 pm

Nice one! a man after my own heart , hope you find a dial .

Sideband · 12th May 2020, 8:55 pm

Well done! It's going to confuse anyone who comes across it in the future trying to match it to the circuit!

jonnybear · 13th May 2020, 1:44 pm

I have followed pretty much the same design obvious pin outs will be different,
the CBL31/EBL31 replacement using two valves is very simple you just join all the cathodes together eb91 and whatever output valve you have, will put circuit diagram (modified) in the cabinet when finished. Any way it is part of our religion to find faults and make do with what is available, I am quite surprised how well it works though SW is not brilliant.
John

jonnybear · 17th May 2020, 3:20 pm

If anyone out there has a scan for the dial of this 48A it would be appreciated.
John

jonnybear · 25th May 2020, 6:55 pm

Just a follow up, looking at the characteristics of the EBL31 I found the 6CH6 valve was very similar minus the diodes of course, so I thought I would give it a go and replace the EL90 Russian 9 pin for a 6CH6, the radio now has a lot more volume and gain and short wave is not so silent anymore, so if you have a faulty EBL31 it would be easy to make up a little sub chassis with a 6CH6 and EB91 and wire it to a Octal base keeping the radio authentic and working.
John

slidertogrid · 25th May 2020, 8:00 pm

Quote:

Originally Posted by jonnybear

If anyone out there has a scan for the dial of this 48A it would be appreciated.
John

Well done with that! It is really nice to see a wreck saved! what size is the dial glass you need? I have a Pye dial glass with three vertical scales LW on the left MW in the middle and SW on the right. It measures 19CM wide by just a few MM short of 19CM high. I don't think it is from a 48A but if it will fit it is yours for the cost of the postage.

Rich.

Edward Huggins · 26th May 2020, 11:20 am

I was wondering just how much output you would get from the EL90 just being driven just by the diode. Given you converted to 6.3V heaters, would not the higher-slope EL84 have been better?

jonnybear · 26th May 2020, 1:11 pm

Quote:

Originally Posted by slidertogrid

Quote:

Originally Posted by jonnybear

If anyone out there has a scan for the dial of this 48A it would be appreciated.
John

Well done with that! It is really nice to see a wreck saved! what size is the dial glass you need? I have a Pye dial glass with three vertical scales LW on the left MW in the middle and SW on the right. It measures 19CM wide by just a few MM short of 19CM high. I don't think it is from a 48A but if it will fit it is yours for the cost of the postage.

Rich.

Hi Rich

Have just measured my destroyed glass it measures 19cm wide by 16cm tall so may fit, I will PM you many thanks.
John

jonnybear · 26th Sep 2020, 8:56 am

Hi Rich thanks for the offer of your dial unfortunately it will not fit as it is part of a cut out in the cabinet,so still looking for a dial or scan, also looking for a
PYE baby QU mains radio, which will take me back to my childhood, all costs met.
John

12th May 2020, 12:17 pm	#1
jonnybear Octode Join Date: Nov 2010 Location: Cullompton, Devon, UK. Posts: 1,435	Pye 48A from the grave to life Living in lockdown I dug out this old 48a I was given as a wreck while having a clear out, no valves, valve bases broken, smoothing cap exploded, no dropper or dial cabinet covered in paint, was just going to scrap it when I thought rather than sitting around I will make it a little project. Replacing valve bases with B9A using ECH81,(CCH35) EF85,(EF39) EB91, and EL90 (CBL31)Russian 9 pin rewired recapped fitted mains transformer for heaters and whalla one working radio,the loudspeaker was OK, now to find a dial a back and strip the cabinet. John Attached Thumbnails

12th May 2020, 1:43 pm	#2
rojosuiza Tetrode Join Date: Mar 2018 Location: Amsterdam, Netherlands Posts: 68	Re: Pye 48A from the grave to life Nice title, good work.

12th May 2020, 3:58 pm	#3
vinrads Dekatron Join Date: Feb 2009 Location: Chesterfield, Derbyshire, UK. Posts: 3,762	Re: Pye 48A from the grave to life Nice one! a man after my own heart , hope you find a dial .

12th May 2020, 8:55 pm	#4
Sideband Dekatron Join Date: Oct 2003 Location: Croydon, Surrey, UK. Posts: 7,572	Re: Pye 48A from the grave to life Well done! It's going to confuse anyone who comes across it in the future trying to match it to the circuit! __________________ There are lots of brilliant keyboard players and then there is Rick Wakeman.....

13th May 2020, 1:44 pm	#5
jonnybear Octode Join Date: Nov 2010 Location: Cullompton, Devon, UK. Posts: 1,435	Re: Pye 48A from the grave to life I have followed pretty much the same design obvious pin outs will be different, the CBL31/EBL31 replacement using two valves is very simple you just join all the cathodes together eb91 and whatever output valve you have, will put circuit diagram (modified) in the cabinet when finished. Any way it is part of our religion to find faults and make do with what is available, I am quite surprised how well it works though SW is not brilliant. John

17th May 2020, 3:20 pm	#6
jonnybear Octode Join Date: Nov 2010 Location: Cullompton, Devon, UK. Posts: 1,435	Re: Pye 48A from the grave to life If anyone out there has a scan for the dial of this 48A it would be appreciated. John

25th May 2020, 6:55 pm	#7
jonnybear Octode Join Date: Nov 2010 Location: Cullompton, Devon, UK. Posts: 1,435	Re: Pye 48A from the grave to life Just a follow up, looking at the characteristics of the EBL31 I found the 6CH6 valve was very similar minus the diodes of course, so I thought I would give it a go and replace the EL90 Russian 9 pin for a 6CH6, the radio now has a lot more volume and gain and short wave is not so silent anymore, so if you have a faulty EBL31 it would be easy to make up a little sub chassis with a 6CH6 and EB91 and wire it to a Octal base keeping the radio authentic and working. John

26th May 2020, 11:20 am	#9
Edward Huggins Dekatron Join Date: Sep 2015 Location: Southwold, Suffolk, UK. Posts: 8,328	Re: Pye 48A from the grave to life I was wondering just how much output you would get from the EL90 just being driven just by the diode. Given you converted to 6.3V heaters, would not the higher-slope EL84 have been better? __________________ Edward.

26th Sep 2020, 8:56 am	#11
jonnybear Octode Join Date: Nov 2010 Location: Cullompton, Devon, UK. Posts: 1,435	Re: Pye 48A from the grave to life Hi Rich thanks for the offer of your dial unfortunately it will not fit as it is part of a cut out in the cabinet,so still looking for a dial or scan, also looking for a PYE baby QU mains radio, which will take me back to my childhood, all costs met. John