Trio 9R59D receiver - UK Vintage Radio Repair and Restoration Discussion Forum

Phil G4SPZ · 11th Jan 2019, 12:51 pm

I have been advising Forum member Trevor (‘Humpty Dumpty’) via several PMs how to repair various faults on his newly-acquired receiver. So far, he has successfully replaced the volume control and the receiver is working, but with constant hum. He has established that the HT at the anode of the output valve is only about 40 volts instead of the normal 200 volts. I have now asked Trevor to measure the valve’s cathode voltage to see whether the low HT is being caused by excessive current draw through the output valve or simply by a faulty reservoir capacitor.

I have suggested starting a new thread here to enable others to contribute and/or benefit as the repair process proceeds.

Phil

Station X · 11th Jan 2019, 1:33 pm

Quote:

Originally Posted by Phil G4SPZ

I have suggested starting a new thread here to enable others to contribute and/or benefit as the repair process proceeds.

Phil

Good idea.

Is this the early version with the large horizontal tuning scale or a later DE or DS version with round main and bandspread tuning controls?

EDIT. To avoid a proliferation of threads about the same radio it would be best to continue the discussion in this thread:-

https://www.vintage-radio.net/forum/...d.php?t=152795

Phil G4SPZ · 11th Jan 2019, 2:00 pm

Thanks Graham. I had no idea Trevor had started another thread! Please close this one and I will migrate to the other thread, with a bit of an update. Kind regards,

Station X · 11th Jan 2019, 2:04 pm

Thanks Phil.

I have a 9R59DS should you require anything checking. The voltages in the service sheet aren't entirely accurate even allowing for the increased sensitivity of modern meters.

4OV on an anode is low though!

Thread closed.

11th Jan 2019, 12:51 pm	#1
Phil G4SPZ Dekatron Join Date: Apr 2005 Location: Bewdley, Worcestershire, UK. Posts: 4,748	Trio 9R59D receiver I have been advising Forum member Trevor (‘Humpty Dumpty’) via several PMs how to repair various faults on his newly-acquired receiver. So far, he has successfully replaced the volume control and the receiver is working, but with constant hum. He has established that the HT at the anode of the output valve is only about 40 volts instead of the normal 200 volts. I have now asked Trevor to measure the valve’s cathode voltage to see whether the low HT is being caused by excessive current draw through the output valve or simply by a faulty reservoir capacitor. I have suggested starting a new thread here to enable others to contribute and/or benefit as the repair process proceeds. Phil __________________ Phil Optimist [n]: One who is not in possession of the full facts

11th Jan 2019, 2:00 pm	#3
Phil G4SPZ Dekatron Join Date: Apr 2005 Location: Bewdley, Worcestershire, UK. Posts: 4,748	Re: Trio 9R59D receiver Thanks Graham. I had no idea Trevor had started another thread! Please close this one and I will migrate to the other thread, with a bit of an update. Kind regards, __________________ Phil Optimist [n]: One who is not in possession of the full facts

11th Jan 2019, 2:04 pm	#4
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,286	Re: Trio 9R59D receiver Thanks Phil. I have a 9R59DS should you require anything checking. The voltages in the service sheet aren't entirely accurate even allowing for the increased sensitivity of modern meters. 4OV on an anode is low though! Thread closed. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.