Re: PRF Members Tech Journal

161
What's easier than doing some sheet metal fabrication to make or modify the top/bottom panels of a Garrison Keillor (h/t FM Nate Dort) 400RB? Paying someone else to do it? OK, but what's even easier than that?

Not doing it!

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Of course this means the back panel (and therefore the entire power amp) is only held in place by four (4) 6-32 screws, instead of twenty-four (24). But at least you can't stick your hand in it now.

I did swap the (already repaired once?) power cord for a new one, with an intact ground pin! The question mark regarding prior repairs is because the hot lead was soldered directly to the switch, which caused me to almost break the switch as I pulled on the un-shrunk heat shrink thinking it was another crimp-on quick connect:

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I still haven't received the 5A fuses I ordered (RIP Radio Shack(?)) but the 2A I put in there hasn't blown yet. I suppose I'll find out at practice tonight.

The downside of repairing the ground connection is that the amp's noise floor increased. A trade-off I'm willing to make if it decreases the accidental electrocution odds.

Re: PRF Members Tech Journal

162
A pretty weaksauce "tech journal" post (5 solder joints and a setup) but I started restoring the shortscale bass I picked up the other week. It played OK but both pickups were disconnected. The bridge "humbucker" (pretty sure it's a single with 2 rows of screws) needs a mounting ring so it's in the "to do" basket.
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Wired up the neck pickup - another single coil under a big square dummy cover - but nothing at all. Turns out the windings were broken away from the leads.
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After three attempts and one of the most frustrating solder jobs I've ever done, I got it sorted out, I hope for good, and got a click when I tapped it.
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Put it all back together, restrung it with the ancient flats, BINGO.
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Still to do: make a pickup ring and a back cover plate.

Re: PRF Members Tech Journal

163
I used to love the pedal steel. Then I got one. Played it for a few years, got to where I could fake it. Now guess what everybody wants you to play. And then guess who just fucked up theirs on a stupid string change.

I finished destroying a tuner that shipping originally damaged, now my pedals don’t work and I have two unison B strings right next to each other.

I have to get more strings in before I can really do anything to fix it, but I tried to record a parr anyways and now the guitar sounds just like Big Star’s 3rd. Ok!

Re: PRF Members Tech Journal

165
Got ahold of a "Jazzcaster" body a couple few whiles ago. I am attempting to apply fabric to the body with some titebond and a roller.

I will have pics as soon as I find a hosting site that isn't shit assed.


Anybody got recs for a finish/sealer that I can apply afterwards? I'm only seeing pro shops with the whole spray apparatus and room doing it.

Is sealer something I can get in a rattle can?
New metal outfit

https://laddermatchco.bandcamp.com/album/3-count-demo

Re: PRF Members Tech Journal

166
Wired together and boxed up an overly-complicated OD/boost-type-thing last night, sounds pretty solid!
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It's a SHO-ish boost into a light-medium gain OD + 2-band EQ into a final diode-biased MOSFET boost. The pre and post boosts are on the same switch so you can control how hard the front end is slammed, and then adjust the volume boost to taste. There's also a voltage starve for one of the stages which gets into sputtery gated territory; with the starve cranked, everything else dimed, and the bass rolled back it kinda does the J&MC thing, which is cool.

It's kind of Zvex-y, but uses LND150 depletion-mode MOSFETS instead of BS170 enhancement mode devices.

7-knobs on stripboard is too many knobs!

Re: PRF Members Tech Journal

170
Nice. A lot of transistors in an amp style circuit. Is it noisy? Do you care ;)

The voltage starve is only for one stage?

How did you chose the value for the drain resistors? It just looks weird seeing such a low value on the drain that is then followed by high impedance, tube amp style component values.
If it sounds good it is good, and it does look similar to other "FET amp in a box" circuits. But I've been doing a lot of secret work involving load lines and input/output impedance of tube stages and... oww my head.

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