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Dynaco FM-3 revival
#7

Thanks guys! I'm still working with this, but running into a couple issues that you might have already been through. I followed the instructions - mostly - ... I started with the IF as described in the instructions. All tubes tested good, exc the GT 12AX7, which I replaced. Showed partial short when warm. That aside, I tuned between stations and listened to the hiss like the instructions said, then touched up the alignment. The bottom slugs on T2 and T1 seemed to really bring it in.

Now - here's where I stopped and need a little advice. When I tune in a station, I have to detune it slightly to get it to come in - meaning, if the eye tube is fully closed, it is about half muted and no stereo indication. If I slightly detune, then it comes in clearer and the stereo indicator comes on.

Next - the discriminator. I haven't touched it yet, instructions say to detune the top slug and adj the bottom slug, but step 24 on the alignment says to tune a station to peak, check the #31 voltage for -11. Reading on, you set for zero. Ok, so I just did a check - with the tuning eye fully closed, it's off. Way off. But - if I detune the station for best reception, then it zeros. So - when they say tune the station for peak, are they meaning clearest signal - or peak eye closing? I think that's where I'm a little confused. If it's peak eye closing - the station kinda mutes, so - adj the coil for zero there? Or, should I redo the IF alignment?

Things just seemed a little off before I started, so is the reason I'm checking this. I truly suspect the Disc trans is off a little, but need a little help before going further,

Edit: I see that lung cancer! I think both are about the same. I suspect the original owner is long deceased. +1 on the quality of the Dynas! Dynaco was my 1st "good" tube setup, found a Pas2x and ST70 in a used stereo store when I was a teenager, and when I got it hooked up and heard how it sounded, I put away my Akai solid state separates and never looked back! In fact, I still use my Pas 2x, and my 70 still comes on and sounds great! My favs tho are with my Mk 3s.

If I could find the place called "Somewhere", I could find "Anything" Icon_confused

Tim

Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44


Messages In This Thread
Dynaco FM-3 revival - by TV MAN - 04-28-2026, 09:24 AM
RE: Dynaco FM-3 revival - by TV MAN - 04-28-2026, 09:30 AM
RE: Dynaco FM-3 revival - by morzh - 04-28-2026, 10:26 AM
RE: Dynaco FM-3 revival - by TV MAN - 05-01-2026, 12:10 AM
RE: Dynaco FM-3 revival - by morzh - 05-01-2026, 02:26 PM
RE: Dynaco FM-3 revival - by MrFixr55 - 05-02-2026, 01:29 AM
RE: Dynaco FM-3 revival - by TV MAN - 05-25-2026, 12:10 AM
RE: Dynaco FM-3 revival - by morzh - 05-25-2026, 11:49 AM
RE: Dynaco FM-3 revival - by TV MAN - 05-27-2026, 10:21 AM
RE: Dynaco FM-3 revival - by morzh - 05-27-2026, 10:24 AM
RE: Dynaco FM-3 revival - by radiorich - 06-16-2026, 01:28 AM
RE: Dynaco FM-3 revival - by TV MAN - 06-22-2026, 02:38 PM
RE: Dynaco FM-3 revival - by radiorich - 06-22-2026, 04:13 PM
RE: Dynaco FM-3 revival - by TV MAN - 06-26-2026, 10:50 AM
RE: Dynaco FM-3 revival - by TV MAN - 06-26-2026, 10:18 PM
RE: Dynaco FM-3 revival - by MrFixr55 - 06-27-2026, 12:30 AM
RE: Dynaco FM-3 revival - by radiorich - 06-27-2026, 01:55 AM
RE: Dynaco FM-3 revival - by TV MAN - 07-05-2026, 03:17 PM
RE: Dynaco FM-3 revival - by Arran - 07-06-2026, 08:21 PM
RE: Dynaco FM-3 revival - by TV MAN - 07-08-2026, 02:02 PM



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