PYE Q4 Jewel case audio stage - UK Vintage Radio Repair and Restoration Discussion Forum

Turnbull · 11th Jun 2021, 11:04 am

My Pye Q4 has just stopped working. The speaker was making faint popping sounds. I found that the output transformer appeared quite warm and the supply voltage was much lowered than 9V. I think it could be the audio transformer, but its resistance readings appear to be ok. I have used an earpiece and can trace the radio signal all the way from the AF stage and out of the AB amplifier transistors. Any ideas? I have ordered a transformer from RS as suggested in one of the website pages but its not arrived yet. Many thanks for reading

Cobaltblue · 11th Jun 2021, 11:15 am

Hello and welcome to the forum.

There are two versions of this set a 6 transistor and a 7 transistor.

Either way it looks as if the output transistors are drawing too much current.

Do you have a multimeter?

the service data is available for both types here.

https://www.service-data.com/search....&search=Search

Cheers

Mike T

11th Jun 2021, 11:04 am	#1
Turnbull Diode Join Date: Jun 2021 Location: Knebworth, Hertfordshire, UK. Posts: 1	PYE Q4 Jewel case audio stage My Pye Q4 has just stopped working. The speaker was making faint popping sounds. I found that the output transformer appeared quite warm and the supply voltage was much lowered than 9V. I think it could be the audio transformer, but its resistance readings appear to be ok. I have used an earpiece and can trace the radio signal all the way from the AF stage and out of the AB amplifier transistors. Any ideas? I have ordered a transformer from RS as suggested in one of the website pages but its not arrived yet. Many thanks for reading

11th Jun 2021, 11:15 am	#2
Cobaltblue Moderator Join Date: Dec 2010 Location: Exeter, Devon and Poole, Dorset UK. Posts: 6,865	Re: PYE Q4 Jewel case audio stage Hello and welcome to the forum. There are two versions of this set a 6 transistor and a 7 transistor. Either way it looks as if the output transistors are drawing too much current. Do you have a multimeter? the service data is available for both types here. https://www.service-data.com/search....&search=Search Cheers Mike T __________________ Invisible airwaves crackle with life or at least they used to Mike T BVWS member. www.cossor.co.uk