Thanks Don, You're right, my email was a little ambiguous. I am using the 'Continuity' tester on my DVM to get a relative (between relays) idea of what I should see. As you pointed out, it's difficult to make accurate resistance readings across relays. The continuity tester has a fixed tolerance for resistance, and if it reads 0v +/-[tolerance] it beeps indicating that the points the probes are touching within the same circuit and that there is no resistance between them.
Given the above, positive means I get a beep (same circuit, no resistance) and and negative means no result (resistance between points > 0 +/-tolerance). This is a crude way of testing, but it gives me an indication of what I should be seeing with respect to the other relays in the stage. The 'beep' is a benchmark for low/high, and is a constant value. Believe me, I've never been mistaken for an engineer ;) So all that being said, I get a beep on pins 3 and 8 on every other relay, but the 40 meter does not beep. It's an inconsistency that I can't explain, and so I will defer to minds greater than my own. Help! :) Thanks for all of your help, Jim --- [email protected] wrote: From: Don Wilhelm <[email protected]> To: [email protected] CC: Elecraft reflector <[email protected]> Subject: Re: [Elecraft] 40m relay in K2 LPF stage - sorry if this is blank Date: Mon, 02 Mar 2009 14:56:49 -0500 Jim, I don't understand your terminology. In most common usage, positive and negative have nothing that relates to continuity - a continuity measurement is usually expressed as an amount of resistance (usually low) between two points. Alternately, the conductivity can be expressed in mhos, the inverse of resistance, but that is not normally used except in engineering. As for making relay measurements in the Low Pass Filter area, every point will have a very low DC resistance to ground because T4 lead 3 is permanently connected to the LPF and the other lead of that winding (lead 4) is connected to ground. One must lift either lead 3 or 4 of T4 in order to make meaningful resistance or continuity measurements in the LPF. 73, Don W3FPR Jim Giercyk wrote: > All, > > I seem to have lost receive on 40m on my K2 (rev A, no 60m), and I am > thinking that I have a bad relay in the LPF stage. I'm seeing some strange > readings and wanted to get a consensus before attempting to remove a relay. > So, here is what I see: > > With power off, measuring for continuity with W1, pins 3, 7 and 8 on the > relay are negative. However, pins 2, 4 and 9 are positive. That makes no > sense. With the power off, shouldn't 3 and 8 be positive? Time for a new > relay?? > > Thanks, > > Jim > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
