Bottlehead Forum

Bottlehead Kits => Eros Phono => Topic started by: olegreg on November 21, 2022, 09:19:27 AM

Title: Missing voltages [resolved]
Post by: olegreg on November 21, 2022, 09:19:27 AM

I am doing post assembly tests. Resistances were fine.
DC volts at 1A & 1B fine
OA thru OkB all are 0 VDC
Whats up?
Greg
 

Title: Re: Missing voltages
Post by: Paul Birkeland on November 21, 2022, 12:56:18 PM

This is most likely a soldering issue on that front C4S board.

Title: Re: Missing voltages
Post by: olegreg on November 28, 2022, 08:56:50 AM

You were correct, I found a couple bad solder joints on my 3rd inspection.
New issues on separate post.

Title: Re: Missing voltages again
Post by: olegreg on December 01, 2022, 06:08:07 AM

I went to run the system this morning and no sound or anything from EROS 2. All VDC are good except OKA & OKB
which are at 0 VDC. It ran perfectly last evening.
I am at a loss...

Title: Re: Missing voltages
Post by: Paul Birkeland on December 01, 2022, 06:12:38 AM

I would be looking at the shielded twisted pair wiring that feeds pins 4 and 5 on each of those sockets.  That's about all the EF86s share between the two, and something like this is likely a flaky solder joint.

Title: Re: Missing voltages
Post by: Doc B. on December 01, 2022, 08:50:28 AM

Maybe remove and reinsert the tubes too. Might clean some oxidation off and/or help to show where a weak joint on one of the tube socket terminals is.

Title: Re: Missing voltages
Post by: olegreg on December 01, 2022, 02:09:21 PM

You guys nailed it! I re-flowed all the heater connections and yes, that did it.
Thank you, gentlemen.