Rick;
For at least the past 12-14 months, we have received 1N4007 diodes
"direct replacement for 1N4002" and do not have a valid reason why this
has become a "sub" from 3 vendors we use.
Good luck,
Jim Miller, K4SQR
http://www.comteksystems.com
4-Square Experts, Stack Yagi
& Remote Antenna Switching Systems
On Sun, 27 Jul 2003 08:38:20 -0700 "Rick Williams"
<rick.williams@telus.net> writes:
> Steve the schematic shows that 1N4007s are the diodes of choice.
>
> Now that I have the rig apart I can report that of the 14 diodes
> used to
> switch the 7 band combinations 1 is a 1N4007 and the rest are, I
> assume, the
> surface mount equivalent.
>
> I'm trying to figure out how a rig that has never had the case off
> it has a
> 1N4007? Perhaps the board failed a test after production and the
> repair
> crew only had discrete components rather than surface mount parts!
>
> By the way, I've now determined that the problem IS a diode failure
> (one of
> the surface mount diodes).
>
> 73,
>
> Rick
> VE7ASR
>
> Web site: http://www3.telus.net/ve7asr
>
> > ----- Original Message -----
> > Steve Baron - KB3MM SteveBaron at StarLinX.com
> > Sun Jul 27 00:27:20 EDT 2003
> >
> > What diodes do they use for that switching?
> >
> > ----- Original Message -----
> > From: "Rick Williams" <rick.williams at telus.net
> > To: "TenTec List (E-mail)" <TenTec at contesting.com
> > Sent: Saturday, July 26, 2003 16:01
> > Subject: [TenTec] Update - Argo V low output
> >
> >
> > Well this time I think I have found the problem! After measuring
> the
> > voltage at a reasonably accessible area of the transmitter
> switching
> circuit
> > it looked to me like the 80 meter switch was always on. The
> readings on
> the
> > various coils were correct when the rig was on 80 metres but
> screwy on the
> > other bands. (If anyone wants the details please feel free to
> contact me
> > directly.)
> >
> > I discussed my analysis with Paul Clinton (WD4EBR, Service
> Manager) and
> > others at Ten-Tec and they agreed that the 80 metre circuitry was
> likely
> the
> > problem. A shorted switching diode or a shorted transistor the
> culprit.
> > They hope to get a "Care Package" with the appropriate parts into
> the mail
> > early next week. I will now begin the dismantling process.
> >
> > But before I put this item to rest I have some comments to add:
> >
> > 1) Thanks to all on the reflector for your assistance and
> insight.
> > 2) Thanks to Ten-Tec for the prompt response to my problem.
> > 3) A 2nd thanks to Ten-Tec for a great manual (explaining all
> the
> > circuitry in plain language) and complete schematics.
> > 4) Finally, I've learned a lot and that's always fun!
> >
> > Of interest to readers with other rigs were Paul's final words "
> ... don't
> > forget that your efforts to repair the rig will NOT effect your
> warranty!"
> >
> > (In a few days I'll be posting pictures of the Argo V surgery on
> my
> website
> > for those that may be interested.)
> >
> > 73,
> >
> > Rick
> > VE7ASR
> >
> > Web site: <http://www3.telus.net/ve7asr>
> >
>
>
>
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>
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