[MRCA] Hamfest DVM modules

B. Smith smithab11 at comcast.net
Sun May 8 09:29:55 EDT 2016


Be Sure and check for RF noise before doing any final installation.
Couple of ferrite beads on the leads and keep wiring short.
Z

On 5/8/2016 9:10 AM, DSP3 wrote:
> For what its worth, I bought two of those small, pop-in 3-digit, panel 
> mount voltmeters at the Hagerstown fest, yesterday.  No documentation, 
> whatever, is provided.  The idea was to add them to a couple of LV 
> power supplies I have that are meterless.  Well, they don't work very 
> well, at all, I believe. They are powered by about 3-9v DC.  The ones 
> on display appeared to be just fine.  I wired both of them up to 
> batteries and power supplies and, with proper Vcc applied, got 
> readings typically 20-30% high along with a 2v-4v instability.  I 
> thought that perhaps the meters were responding to noise and/or ripple 
> but the 9v batteries connected exhibited the same error and 
> instability.  The meters do appear stable with only Vcc applied and 
> indicate 00.0v.   Anyone have any experience with these little DVMs?  
> Is additional filtering required?  Are they maybe AC meters with a 
> high crest factor and a bridge on the input?  I have no idea.......
>
> Jeep - K3HVG
>
>
> ______________________________________________________________
> MRCA mailing list
> Home: http://mailman.qth.net/mailman/listinfo/mrca
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:MRCA at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html



More information about the MRCA mailing list