PYE jewel case Radio - UK Vintage Radio Repair and Restoration Discussion Forum

Johnbarn · 23rd Jun 2020, 3:47 pm

This radio works perfectly on MW but the LW, although pulling in several stations, I can’t get R4 on 1500 m or RTE1 on 1100 m. There are lots of stations being received through the band but not the ones I want.
I've checked the ferrite aerial windings and all look good. The IFT cores look like they haven’t been got at. Where should I look to get LW working as it should?
It looks like a conventional transistor superhet with OC44/45/45, OC81d and OC81x2.
Many thanks for any help, John

paulsherwin · 23rd Jun 2020, 3:52 pm

It sounds as if the radio isn't actually tuning the LW band, as there's very little on LW apart from BBC R4 and RTÉ1. The first thing to do is clean the wavechange switch contacts thoroughly.

Johnbarn · 23rd Jun 2020, 4:38 pm

Thank you for that Paul. I have now checked all switch wafers and also given them a good clean with switch cleaner. Still the same problem. Interestingly I identified one of the supposed LW stations as our local Downtown radio which is on 300 m MW but coming in loud and clear on about 1900 m on the LW dial as well!

paulsherwin · 23rd Jun 2020, 5:02 pm

OK, that suggests that there's some sort of problem with the LW oscillator coil.

Johnbarn · 23rd Jun 2020, 6:13 pm

Is that the one on the pcb but with just exposed wiring and no cover?

paulsherwin · 23rd Jun 2020, 6:28 pm

Yes, probably.

Nuvistor · 24th Jun 2020, 9:28 am

There is a circuit in RM for a transistor Pye Jewel case Radio. If it’s the same one there is only one oscillator coil, it is set for MW and an extra capacitor and trimmer are switched in to lower the LO frequency for LW reception.

G8UWM-MildMartin · 24th Jun 2020, 3:00 pm

If it is one of the ones with a frame aerial in the lid, it is worth checking the continuity of the ribbon cable.

Johnbarn · 24th Jun 2020, 10:06 pm

Thank you everyone. Mine is the Q4 model without frame aerial. I have checked the oscillator coil continuity by removing it and replacing it and all was well. Radio still works well on MW. I then concentrated on the ferrite aerial coils which don’t exactly look like the the circuit diagram in that the external aerial doesn’t have its own winding (L3) but is across L4 which looks like the LW one. I’m still working on the radio stage by stage but so far still no LW. Work continues!!

paulsherwin · 24th Jun 2020, 11:30 pm

If this radio does indeed use the MW osc coil with a padder cap for LW, then the padder cap may be bad.

23rd Jun 2020, 3:47 pm	#1
Johnbarn Pentode Join Date: Feb 2015 Location: Belfast, Northern Ireland, UK. Posts: 130	PYE jewel case Radio This radio works perfectly on MW but the LW, although pulling in several stations, I can’t get R4 on 1500 m or RTE1 on 1100 m. There are lots of stations being received through the band but not the ones I want. I've checked the ferrite aerial windings and all look good. The IFT cores look like they haven’t been got at. Where should I look to get LW working as it should? It looks like a conventional transistor superhet with OC44/45/45, OC81d and OC81x2. Many thanks for any help, John

23rd Jun 2020, 3:52 pm	#2
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,970	Re: PYE jewel case Radio It sounds as if the radio isn't actually tuning the LW band, as there's very little on LW apart from BBC R4 and RTÉ1. The first thing to do is clean the wavechange switch contacts thoroughly.

23rd Jun 2020, 4:38 pm	#3
Johnbarn Pentode Join Date: Feb 2015 Location: Belfast, Northern Ireland, UK. Posts: 130	Re: PYE jewel case Radio Thank you for that Paul. I have now checked all switch wafers and also given them a good clean with switch cleaner. Still the same problem. Interestingly I identified one of the supposed LW stations as our local Downtown radio which is on 300 m MW but coming in loud and clear on about 1900 m on the LW dial as well!

23rd Jun 2020, 5:02 pm	#4
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,970	Re: PYE jewel case Radio OK, that suggests that there's some sort of problem with the LW oscillator coil.

23rd Jun 2020, 6:13 pm	#5
Johnbarn Pentode Join Date: Feb 2015 Location: Belfast, Northern Ireland, UK. Posts: 130	Re: PYE jewel case Radio Is that the one on the pcb but with just exposed wiring and no cover?

23rd Jun 2020, 6:28 pm	#6
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,970	Re: PYE jewel case Radio Yes, probably.

24th Jun 2020, 9:28 am	#7
Nuvistor Dekatron Join Date: Aug 2013 Location: Wigan, Greater Manchester, UK. Posts: 9,433	Re: PYE jewel case Radio There is a circuit in RM for a transistor Pye Jewel case Radio. If it’s the same one there is only one oscillator coil, it is set for MW and an extra capacitor and trimmer are switched in to lower the LO frequency for LW reception. __________________ Frank

24th Jun 2020, 3:00 pm	#8
G8UWM-MildMartin Heptode Join Date: Jan 2004 Location: Stockport, Greater Manchester, UK. Posts: 827	Re: PYE jewel case Radio If it is one of the ones with a frame aerial in the lid, it is worth checking the continuity of the ribbon cable.

24th Jun 2020, 10:06 pm	#9
Johnbarn Pentode Join Date: Feb 2015 Location: Belfast, Northern Ireland, UK. Posts: 130	Re: PYE jewel case Radio Thank you everyone. Mine is the Q4 model without frame aerial. I have checked the oscillator coil continuity by removing it and replacing it and all was well. Radio still works well on MW. I then concentrated on the ferrite aerial coils which don’t exactly look like the the circuit diagram in that the external aerial doesn’t have its own winding (L3) but is across L4 which looks like the LW one. I’m still working on the radio stage by stage but so far still no LW. Work continues!!

24th Jun 2020, 11:30 pm	#10
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,970	Re: PYE jewel case Radio If this radio does indeed use the MW osc coil with a padder cap for LW, then the padder cap may be bad.