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I assume you're putting in the 105 volts through a variac, right? Ned If you are using a variac you should also be mindful of your filament voltage. If your line was normally 117VAC and you bumped it down using a variac, unless you are running a separate filament supply, all your heaters will be un...

paully wrote: With everything connected, I'm hitting the right voltages, but at 105 VAC

Congratulations! but why is your line voltage so low?

The first 22k resistor in the PSU looks like it should be 2.2k.

The screen supply is also omited from the PSU. The schematic suggests that the screens are not in series with the rest of the rails in your supply. If that's the case I would recommend arranging all resistive PSU elements in series.

Why not just look at some pultec schematics?

you can't polish a turd

Anytime.

You might want to ask if he has 500pf just for the hell of it. But i think 540 will work well.

wow, thats pretty over the top. i like how his coils are wound into spider web like structures. Ok guys if I use a 365pf variable cap, how would that effect the value of the inductor which is 200uh for a 500 pf cap. P.S. I can't believe you can't get the 500pf variable cap as a ceramic?! sayer Here...

Sayer wrote:just since this IS the diy forum I thought I 'd post this page I saw about making your own variable capacitors.

http://www.eham.net/articles/5217

That seems like a lot of trouble to go through for something you could easily order.

Check out this guy's radio sets...

http://www.schmarder.com/

Just because the The Sylvania's are NOS I wouldn't rule out the possibility of microphonics. It does happen. you might want to try some other tubes. did you let them cook?

Do you have a schematic?

Leeds Radio definitely has them. it's the air gapped type used for tuning. Don't go by the website. it's only a fraction of what they have in there

www.leedselect.com

Radiotron is way advanced for beginners getting into tubes. and expensive too. not to mention that there are 4 different editions. 3 (thin) and 4 (very heavy) are the ones to get. RC-3O (which is mentioned) is great for learning about fundamentals of resistance coupled and direct coupled tube applic...

You mentioned that your B+ is 225v, so I take it you have the tube version of these pre's. Did you try changing out the tubes? Microphonic tubes often let out a high pitch tone similar to what you are describing. One thing you could try is to power up the unit with the cage off and very carefully an...