Crawls Backward (When Alarmed)

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Trouble in Dynaco -Land

Uh oh.


The PAS has four AC 'convenience' outlets on the back.   Two of 'em are switched, and two are unswitched.  (Switched meaning they are live only when the preamp is switched on).  They are truly a convenience for Yr Fthfl Blggr because he...I....use them for the amp (a Dynaco ST-70) and a small fan.

Looks like some dunderhead broke one of the outlets.  Probably tried to put a polarized plug into one.  Well, it DID work, didn't it?

First things first.  I need to find a replacement for this one.  Second, I need to learn that you can only use non-polarized plugs in these things.

I considered reusing the outlet, but one side of it is dangerously close to touching the chassis.  Too close for comfort.

Luckily I do have a replacement.  Off to the secret stash of Other Dynaco Junk, Robin!

Here we have one Dynaco FM-3 FM tuner chassis.  Not sure if you can read the tape label I put on it, but it says it works, but needs a fuse cap and has a bad rectifier tube.  It's also about to be missing it's AC convenience outlet.  Who knows if I'll ever get around to getting this one going, so I'm going to take the outlet off the FM-3 and use it on the PAS.  This is where having another piece of this junk came in handy.

Quick side note/history lesson.  Remember when I was talking about the Dynaco numbering system for their PC boards?  Here's another case in point.  The FM-3 has three PC boards, numbered PC-7, PC-8 and PC-12.

Just thought I'd point that out.

And man, do these look grungy.  Bill Thomas is talking about starting to make replacement boards for the FM-3 - and I will buy some as soon as they are available.

The FM-3 is a pretty amazing little device.  It too was available as a kit and it's unique in the fact that it can be totally aligned with nothing more than an alignment tool and a VTVM (Vacuum Tube Voltmeter).  It's still revered for its fine sound.  I love my main one, and Ms. Yr Fthfl Blggr too says it sounds great.

There is a ton of information about the FM-3 on the internet, here's just one positive review.  The only tube tuners that are better are the McIntosh (es) and the legendary Marantz 10B.  But the FM-3 can't be beat for the money.  I occasionally window-shop the McIntosh MR 65,  MR 67 and MR 71, and would love to have one, but the prices make me pass out.  Maybe one day I'll get lucky at a yard sale.

But back to the project at hand.

Here's the back panel of the FM-3.  You can see it has just one AC outlet.  I actually use this too on my "production" FM-3 to drive a small ventilation fan that only comes on when the tuner is on.

You can also see the missing fuse cap to the left.  This one actually works - not sure how somebody lost it.  But luckily I have a small parts drawer full of 'em.  :-)

Sacrifices must be made in the name of restoration, so here we go.

I left out all the detail shots, but it's pretty much an easy job of desoldering the old outlet, and bolting the new one on.  Here's the new one in place on the PAS.

And on we go...


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