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I need a Bias Probe other than SwAmp

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4/12/2000 5:21 PM

I need a Bias Probe other than SwAmp

Howdy, I'm in desperate need for a bias probe. I've taken on the job of amp tech for two local bands and I really don't have time to be pulling chassis'. I ordered one from Swamp a month ago and have gotten nowhere. I won't get into it here, nontheless I need a Bias Probe quickly. I know Svetlana makes one but theres has a built in meter I don't really need and as this isn't a paid job, don't really want to spend big bucks. Any info appreciated, also, anyone with any info on Charles at Swamp please e-mail me. I don't know what to do about that. Thanks

4/12/2000 5:46 PM
R.G.	I have a DIY article on GEO on building your own bias probe from easily available parts. You might want to take a look. Check under the "Guitar Amps" pages for "DIY Bias Probe".

4/13/2000 11:02 PM
Jethro Tull Bodine	made one!! works great!! thanx Jethro

4/14/2000 5:30 AM
Carl Z	Made one here with an analog meter. You need a few more parts and you'll need to calibrate it of course. You can scavange a galvanometer from a dead ohmmeter. The cool thing here is that it's self powered. WE DON'T NEED NO STINKING BATTERIES!!!! Regards; Carl Z

4/14/2000 2:58 PM

WE DON'T NEED NO STINKING BATTERIES

Carl:
How did you set up the input to the meter?
I've got a nice 0 to 100 ma meter I scavaged & I've been wary of toasting it by hooking it up wrong. Is this one of those Mr. Ohm mysteries? that still seem to confuse my math challanged grey matter?
I acctually put a switching supply in mine so it runs off a 1.5V battery. A bit of overkill but I couldn't resist it.

Marc

4/14/2000 2:08 AM

Re: I need a Bias Probe other than SwAmp

Charles at SwAMP is Charles Barcellona. Selling those probes is a hobby with him. He's a great guy but he always seems to be behind on his work. I usually get him weeknights after 6, Florida time.

You can e-mail hims but it will take a long time to get a response. Also, he makes or has made those probes in batches and sometimes you have to wait a while for one.

4/14/2000 2:44 AM

i e-mailed the orig. poster about my amp friend mike zak (mzak7@aol.com) of upstate NY--i bought a pair of his home-made bias plug-ins a couple of years back--and if you're not that handy, mike's got it all very effectively set up with a precision resistor, tube socket plug-ins, and contact loops to hook your DMM to. has worked great for me. i contacted mike first -- 'cos i didn't want him to be swamped

-- and he says he has some ready for sale. hope this helps, bill

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