Variac Re-designed..kinda?

[Buzzsaaw]

Hi folks,
Today I received my two new meters from Ebay. An AC voltmeter 1-150Vac and an ammeter for 1-10amps AC.

I decided to incorporate a DBT (Dim Bulb Tester) into my old Variac. The box had plenty of room and it would free up some space on my over crowded workbench.

So.. here goes..



The case is an old Telephone test box for a Step by Step type dial office. I ripped out all the old stuff inside. I kept the main panel to mount my stuff on.



Opened up you can see the off an on switch. The outlet above the switch is just straight off of the Variac xformer with no bulb treatment. The AC volt meter and ammeter is to the left. It's fused with a 7 amp fuse right now. That's a little much. In fact the ammeter is a little much too. I should have gone with a 0-3 amp and I may change that out later. I put a CD printer label over the area where the Variac lives. Here I can pencil in voltage or other notes as I go. A little flash glare doesn't help..



The lid has storage space for extra or different wattage lightbulbs. I also have the info on the Variac transformers hookup of the DBT.



And finally the bulb in place and the outlet socket below it is for the Radio under test.

The lid detaches which makes for more bench room and the cord pushes inside the case for storage.

It was a fun project this afternoon and now as soon as I get my order of caps from Canada.. I'll it the grindstone.

The circuit is just an expansion of the one found on this page:
http://www.ppinyot.com/dimbulb/dim_bulb_tester.htm

I tested it on my Hippo and works great! An no.. I barely see the ammeter deflect. .. Oh well...


Buzz

[bandersen]

Very nice
I've been thinking about doing something similar for a while. I have a 150 VAC, 5 amp AC and 10 mA AC meter. Maybe I could make a shunt to turn that into a 1 A AC meter

[Buzzsaaw]

Hi Banderson,
Thanks... I've got to paint the outside now and I'm thinking I'll need to do some sanding on that part. Maybe some racing stripes.

When I change out the Ammeter it might be nice to put in a switch that does a bypass on the meter for something of a heavy load.. greater than 3 amps. That would save the hardware.

Last night I showed some of your vids on Youboob and my relatives were impressed. They think your quite the teacher and technician.!..

Buzz

[Findm-Keepm]

Originally Posted by Buzzsaaw

Last night I showed some of your vids on Youboob and my relatives were impressed. They think your quite the teacher and technician.!..

Buzz

Bob's an author too...

http://www.videokarma.org/attachment...1&d=1290521785



Cheers,

[Buzzsaaw]

Hay.. that's so cool!.. Wow!

I'm going to go pick that up..! I should send it to ya, Bob.. and have U sign it!

Buzz

[Buzzsaaw]

Just got back.. bookstore didn't even show that book in there catalog..(on-line). so I'll have to wait or go to Amazon...

Buzz

[Findm-Keepm]

Buzz,

My apologies - I just now realized you weren't in on the joke - there's a thread I posted back before Christmas of '10 titled "New at Amazon/Barnes and Noble" where I posted the image as an homage to Bob and Phil Nelson, two outstanding restorers and documentarians (is is even a word?).

You've fallen into a GREAT crowd here on VK - take a look at some of the B/W restoration threads Bob has started, particularly his Admiral stuff. Amazing attention to detail, creative resourcefulness, and detailed step-by-step narration.

Sorry once again for the wild goose chase.

Cheers,

[Buzzsaaw]

Oh-Boy!

[bandersen]

I found this article explaining current meter shunts and thought you might find it interesting: http://sound.westhost.com/articles/meters.htm#s4

If you can find an AC meter in the milliamp range, you could use a shunt to scale it's range to something more appropriate for radios. 1 or 2 amps maybe.

I don't there's any way to make a 10 Amp meter more sensitive though.

[Buzzsaaw]

Yes, that is interesting... and Thanks.

Nice site and a good way to save some $$dollars$$ !

Are you re-designing your DBT unit now too?

Buzz

[bandersen]

Not actively, but it's in the back of my mind. I have some cool vintage AC meters, but I need some kind of enclosure

[Buzzsaaw]

I'm allways looking for boxes/cases like the one I found for the Variac. You should have lots of junk and pawn shops around there, being in the "Big City". But I bet they get pounded pretty hard by guys like U and I that are looking for the same stuff.
I'm looking for another box to house my Iso transformer in...So the search goes on.
One place to check is the IT guys at the hospitals. They might have something or know of a test box for an Old X-ray machine that was stuck in the storage room never to be seen again. You never know.
The other place is Ham conventions. But competition is fierce so bring your running shoes and a big duffel bag to carry all the stuff you find in.. Oh.. and lots of Cash money!..
Buzz

[Buzzsaaw]

Instead off an old equipment case as seen above, how about an old Heathkit case.. like the several styles of speakers they made or the Station console units (SB-630).
Here's one.. a smaller style speaker:
http://cgi.ebay.com/Vintage-Heathkit...item2a0fb7c58a
I'm no affiliation to this sale...
It sure would be nice looking on the bench!. A guy could get several and have a whole set of gadgets looking at you.
Buzz

[bandersen]

Thanks for the ideas. back in the good old days, I probably could have easily picked up a metal Bud Box and used a Greenlee punch for the meters.

[Buzzsaaw]

No.. I'm no Art-teest!.. But I drew it up.

What do you guys ('n Gals) use for drawing Schematic drawings?

Here it is:



This is the way it looks now.. Man.. it got heavy too. But it's all in one box and ready to go. The cover comes off (seen above) and it sits nice on my test box shelf above my workbench. I should have added a bell or a whistle... heehee!

Buzz