Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => AmpTools/Tech Tips => Topic started by: stingray_65 on February 23, 2010, 11:59:38 pm

Title: Gaussmeter and Megohm meter
Post by: stingray_65 on February 23, 2010, 11:59:38 pm

I was at one of the antique stores here in town when a guy came in with a box of electronics stuff he said was his dad's who was a amature radio hobbiest.

Well antique store are a far cry from a pawn shop, which I think he was looking for.

I got a few odd tubes a bunch of AARL manuals, but I realy couldn't keep my eyes off the meters.

so for $10 for the box I took it home and and got an

 AEMC model 1026 megohm meter    http://www.professionalequipment.com/aemc-digital-megohmmeter-1026/megohmmeter/?source=pegs

and a Lakeshore model 410 Gaussmeter http://www.lakeshore.com/mag/ga/gm410po.html

Looked them both up and they seem like some high end equipment from thier prices. but I haven't a clue to any practical use I might have for them.

do they have a practical use on my bench?

what the heck does a ham radio operator have use for a gaussmeter?


what uses would I have playing around building amps?

Thanks

Title: Re: Gaussmeter and Megohm meter
Post by: ChrisK on February 24, 2010, 08:45:54 am

I dom't know about the gaussmeter but the megohm meter is usefull for testing for insulation leakage resistance, ie: winding to winding and winding to frame of a transformer that you suspect is shorting outor those old fishpaper circuit cards in fender ampliffiers that you suspect are becoming conductive.  They do a much better test because you test at high voltage (250, 500 or 1000 volts) compared to the 1.5 volt of a VOM which may not be enough to cause the leakage or flash over experienced in HV application.

Another thought is testing tube sockets after you have cleaned and retensioned them.

Title: Re: Gaussmeter and Megohm meter
Post by: sluckey on February 24, 2010, 09:36:49 am

I still use an old Biddle megger (hand crank) for measuring transmission line insulation resistance. Also useful for fishing! Don't know if that digital will catch any fish though.

Title: Re: Gaussmeter and Megohm meter
Post by: jjasilli on February 24, 2010, 03:24:41 pm

Biddle megger (hand crank) . . . Also useful for fishing!

If you're after mega fish:  http://www.google.com/search?q=megafish&rls=com.microsoft:en-us:IE-SearchBox&ie=UTF-8&oe=UTF-8&sourceid=ie7&rlz=1I7SUNA_en

Title: Re: Gaussmeter and Megohm meter
Post by: sluckey on February 24, 2010, 05:40:45 pm

Whoa! Don't think my Biddle would be effective with those fish!

Title: Re: Gaussmeter and Megohm meter
Post by: stingray_65 on February 25, 2010, 12:26:53 pm

So the megohm meter can stay, turns out it has a volt meter ac/dc to 1KV and a very sensitve ohm meter up to 4K.

Think that the gaussmeter could be useful for locating Iron on a chassis?

Not that I've had issues I think before, but I HATE to put something like that I couldn't afford on eBay only to find out I NEED it the next week.

Thanks