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Retired · 11th Sep 2011, 11:51 am

Hi,

First job; sorry Jeffrey the blown Hunts cap was attached to pin4 not pin2 as stated earlier; I've been having a good look around with the spotlight.

I've had a good morning; I snipped the blown cap and re-soldered the connection to the pair of 35R resistors then applied power directly from the mains.

At first I thought everything was dead apart from the glowing valves but turning the volume control brought some very healthy crackles as it did whilst I prodded around under the chassis. I thought I could just detect a very; very light whistle?

Readings at the electrolytics are 170V and 187V.

Readings on PY32; pins 3 & 5 -20V; Pin 4 99V; pin 8 186V.

I had to walk outside to view the CRT through the workshop window but it was blank and I noticed U25 was not lit up either I assume U25 should light up.

I'm wary of taking voltage readings near the LOPT but both 30P4 and U191 were lit up is it OK to take voltage readings on both these valves with my DMM?

Also thanks Jeffrey; I've printed off the full set of TCG316 sheets.

Once again as I don't want to do anything silly I'm in your hands for guidance so please guide away and I'll follow.

Kind regards, Col.

11th Sep 2011, 11:51 am	#78
Retired Heptode Join Date: Mar 2009 Location: Fenay Bridge, Huddersfield. UK. Posts: 673	Re: Restorers dream part 2 the chassis. Hi, First job; sorry Jeffrey the blown Hunts cap was attached to pin4 not pin2 as stated earlier; I've been having a good look around with the spotlight. I've had a good morning; I snipped the blown cap and re-soldered the connection to the pair of 35R resistors then applied power directly from the mains. At first I thought everything was dead apart from the glowing valves but turning the volume control brought some very healthy crackles as it did whilst I prodded around under the chassis. I thought I could just detect a very; very light whistle? Readings at the electrolytics are 170V and 187V. Readings on PY32; pins 3 & 5 -20V; Pin 4 99V; pin 8 186V. I had to walk outside to view the CRT through the workshop window but it was blank and I noticed U25 was not lit up either I assume U25 should light up. I'm wary of taking voltage readings near the LOPT but both 30P4 and U191 were lit up is it OK to take voltage readings on both these valves with my DMM? Also thanks Jeffrey; I've printed off the full set of TCG316 sheets. Once again as I don't want to do anything silly I'm in your hands for guidance so please guide away and I'll follow. Kind regards, Col.