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Old 05-13-2014, 10:14 AM
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NoPegs NoPegs is offline
The glass is -3dB.
 
Join Date: Mar 2014
Location: Amish Country PA.
Posts: 376
It has arrived...

Allrighty! I was surprised to find that the seller did an excellent job of packing it. I had asked to put something firm but squishy between the lid and the dial plate, because in the pictures he listed with it, there were no screws holding the face on. Strangely it arrived with 9 out of 10 screws installed, and the 10th one was discovered inside the cabinet.

I did some quick poking after unboxing it yesterday (Working 3rd shift is a bummer, didn't get delivered until almost 1400, I stayed up for it.) just to get a feel for it. I think the segment of my candohm furthest from the chassis connection is open, but I only grabbed the DMM out of my go-bag to check, and the probes it has are kind of dull and awkward so I'll be double checking that in the next day or so.

The good news seems to be that all windings on the power transformer have what appear to be valid readings of resistance. The main potentiometer also checks out in both overall value and linearity. Bonus points awarded because the mechanical action is nice and smooth too.

My "goat" shields are unpainted and kind of corroded, so I have to figure out how best to polish them up without flattening them out in the process.

There is rust inside, but not anything serious. Going to get a new pot of naval jelly if it doesn't come right off with some steel wool and cutting oil.

I'll see about taking some decently composed pictures, but that might not happen till the weekend.

My initial thoughts are "Well, it turns out to be smaller than my breadbox." I knew they were smaller in person, but when I sent the better half a quick cell pic of it next to my previously mentioned breadbox for scale, she commented on how "cute, but intelligently cute." it is. I quite like it myself, but its good that she approves.


Were the front plates lacquered/shellaced/varnished? Mine has a strong brown tint to it. I prodded it with some denatured alcohol and it comes off, nice and shiny underneath. I honestly can't tell if it's aged shellac or decades of tobacco smoke tar. I just gave it another eyeballing and the inside of the lid has some "condensate" on it. This could be from being stored in a hot attic for years with the lid closed. Baked the shellac off the wood. Might have solved that mystery myself just now.

After stripping the goats off the tubes, it looks like at some point in the past someone "cleaned" the tubes. Neither have markings that I can reveal with any of the usual voodoo. (I haven't tried gold sputtering, although I do have a stash of gold leaf on hand, *mad science cackle*) Obviously the eye-tube is an eye tube. The rectifier is a UX-4 base so probably a 1V, but I can't be certain due to the absence of markings. It's a Sylvania with the really, really old logo. Definitely a rectifier from the internal construction.

I'll admit to only having an emissions type tester, Accurate Instruments Co 257. No UX-4 or UX-6 sockets, and I know I can't make the eye tube do anything with the voltages it supplies, but if I break out the pins and connect the 1V up, 6.3v filament, and test it like one side of a 5U4 or 6X5 (Which I can test with my unit.) I can confirm that it hasn't failed, without blowing it up in the process, right? (After my epic failure at Ohm's law yesterday, I'm kind of spooked now.)

Filaments are good on both tubes, hoping I lucked into a low-hours eye-tube in the process, but I won't know that for a while.

I'll ask the wood ladies what their final answers are, after I take some better lit pictures. The good news is whatever wood it is constructed out of, replicating it will be a trivial task, so you need not remain sans-cabinet much longer, drdave3!

I may end up just lightly steaming mine so it deconstructs, trace out the panels and then glue it up nice and solidly again. It's just a wee bit loose as it sits. I have to think about that.

Has anyone tried to calibrate one of these things? I mean just improving the overall accuracy, not anything excessive like you'd do for a scope or VTVM... Seems to be a calibration pot inside, and the manual mentions factory re-calibration. I'll take any tips I can before pushing into new territory and experimenting myself.


Wow, apologies to anyone who's still reading after the wall of text up there. Thank you!
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