[Boatanchors] how to read microvolts

[Gary Schafer]

While those generators mentioned are very handy and can be used for tuning
things up and measuring levels above a few microvolts they are not good for
making accurate low level signal measurements. They all have too much
leakage and trying to measure below 1 microvolt with them is impossible. The
attenuator reading does go below 1 microvolt but the signal level doesn't
follow because of leakage around the attenuator.
Still much better than the heathkit type generators though. I have a URM-25
that I drag out once in awhile when I need a low frequency signal source.

73
Gary  K4FMX

> -----Original Message-----
> From: boatanchors-bounces at mailman.qth.net [mailto:boatanchors-
> bounces at mailman.qth.net] On Behalf Of Glen Zook
> Sent: Monday, April 02, 2007 1:33 PM
> To: Jim Brannigan; Dick KF4NS; boatanchors at mailman.qth.net
> Subject: Re: [Boatanchors] how to read microvolts
> 
> It is VERY easy to measure microvolt levels without
> expensive laboratory equipment.  There are hundreds of
> thousands of signal generators originally made for the
> commercial two-way market and military uses that have
> well calibrated attenuators that read accurately down
> to well under 1 microvolt.  Those include the
> Measurements model 80 (and the military equivalent
> TS-497 series) and model 180, the Hewlett-Packard
> HP-606 and HP-608 models, the military URM-25 and
> URM-26 models, etc.  All of those models can be found
> for well under $200 and often for less than $50.
> 
> Glen, K9STH
> 
> 
> --- Jim Brannigan <jbrannig at optonline.net> wrote:
> 
> You really can't without expensive lab equipment, but
> why try? Verify that the values in the attenuator(s)
> are correct, measure at the "millivolt" level and do
> the math.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Glen, K9STH
> 
> Website:  http://k9sth.com
> 
> 
> 
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