NUED New Used Equipment Day!!

jtcnj

jtcnj

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Finally let some moths out of the wallet and bought a variac. Most guys on the tube amp forums I frequent advised against the import models in the $65. range.


This used old school Staco is built like a tank. The on -off / voltage select switch is a little wonky but thats an easy fix. $75. delivered.
We happy.

variac.JPG
 
I know what those are but what exactly is its purpose ??? Does this device slowly bring the voltage up on old tube amps and the likes ? yes the old stuff is built good.
 
Exactly, or as part of new build start up as well. You may be able to control the rate at which the magic smoke comes out.
Even amps that have been sitting a few months may benefit from a ramped power up.

I was in the habit of logging my amps running time but got away from it.
Now I plan to make sure they all get run, even at idle, for at least 15 min or so every month.
 
Forgot to mention - One of the other uses (besides as a fan motor speed controller, etc.) is to run the voltage at 110 v ac to simulate the lower wall / receptacle voltages from the 1950's-'60's that the vintagey, Tweed builds in my case, were designed around.
If some magic mojo is found, resistors or diodes can then be employed to adjust the tube plate voltages to taste.
 
Most excellent purchase.
I'd love to have one. Maybe someday...
I still use an old school home made light bulb limiter for start ups.
 
Im still confused........
jtcnj said:
I was in the habit of logging my amps running time but got away from it.
Now I plan to make sure they all get run, even at idle, for at least 15 min or so every month.
Click to expand...

we are supposed to be keeping a "mileage log" of our amp usage?


jtcnj said:
resistors or diodes can then be employed to adjust the tube plate voltages to taste.
Click to expand...

Is that even English?

Hows the coffee pot factor in ----- are you building a time traveling DEvice?
 
You're suppose to be nice to your amps and talk to them real gentle like. Nice Fender! Cute little Vox! Hello my adorable Marshall baby! You know stuff like that! Even a psychotic individual like me does not track hours on my amps. I call that major devotion to gear! Bravo!
 
Hackmaster said:
Most excellent purchase.
I'd love to have one. Maybe someday...
I still use an old school home made light bulb limiter for start ups.
Click to expand...

Yes, agreed, a must have.
I dont plan on using the variac as normal practice to run lower voltage and play; its a tool for specific purposes.
Actually, I plan to re-read my Dave Hunter Guitar Amp Handbook; now a lot more of the details will make more sense.


eSGEe said:
Im still confused........


we are supposed to be keeping a "mileage log" of our amp usage?

Is that even English?

Hows the coffee pot factor in ----- are you building a time traveling DEvice?
Click to expand...

I started to keep the log similar to an equipment run time hour meter, but it fell by the wayside.
I will use it now to track and make sure I plug them all in for a while every month.

Todays higher wall voltages raise the rectified DC voltage (B+ ) the circuit sees.
It changes the character of the amp because it changes the "range" or operating conditions of the tubes.
This is only for comparison for my builds that are using the original circuits, while acknowledging the components are not exactly what those original units were built with.

I thought the coffee pot might come up. It was just a convenient place to plug it in.
I also had a lamp on the counter off to the right to test the unit - the light bulb dims and brightens as you turn the dial, before I put the meter leads on it for the photo.
 
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