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"Wondering now if there is a thermal protect device"




Even if Dynaco felt a thermistor (or similar device) was necessary, I couldn't imagine them winding it inside a transformer.

Just so we're doing an Apples to Apples comparison, tell me if the following measurement methodology is valid compared to your checks.

I have two PAS, but both are assembled, so transformer leads are in circuit.

The primary on one of mine checks 40.5 ohms, the second one checks 45.3 ohms. Your primary checked 110 ohms.

The secondary on my stock PAS, with the 12X4 removed checks: Full winding - 3.04k ohms. Each leg to center tap 1.57k ohms and 1.47k ohms. The second unit's secondary checks almost exactly the same.

Story wrote: Ok, here is what I have:

"Primary - 1.4 ohms

Secondary - 3.05 kohms full winding

1 leg to Center tap - 1.59 k
other leg to CT - 1.46 k

It seems like the significant difference between Story's and my two transformers are the primary impedance. My two are much higher than his 1.4 ohms, but yours is more than double what either of mine check. A high primary impedance would account for low voltages on the secondary for both B+ and the filament.

If yours is faulty, and you're considering the Dynakit Parts transformer as a replacement, I'd email them and ask them what one of theirs checks.

I hope you get this sorted out.

One more thought. You don't happen to have a PA-522 power transformer, do you? As shown below, Dynaco made a PAS transformer which could be wired for either 120 V or 240 V. It's a long shot, and your voltages aren't reduced by the 50% you'd think they'd be if it were wired for 240 VAC, but I thought it was worth a mention.



Edited for poor math skills.



Edits: 12/19/18
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