[Drake] TR-7 problems

[Transmaster]

I pulled and reseated the cards.  I inspected each board and could
find no obvious problems.  I fired it up into a dummy load and with a
tech' Friend on messenger, and  I listening to  the Drake transmitting
to one of my receivers.  The dee-dee-dee is gone, I suspect I may have
had the mic' gain too high with the Electro-Voice 664 I have wired up
for it.  What it sounds like now is a carrier balance, carrier null
problem.  What is the best way of adjusting this, listening on another
radio, an O scope, RF watt meter. The service  manual suggests the
listening method.  I sure hope this is it, but I just can't be this
lucky.

Ken

On 2/15/07, Garey Barrell <k4oah at mindspring.com> wrote:
> Ken -
>
> OK.
>
> Next step is to reseat all cards and connectors.  This wimpy solid-state
> stuff doesn't have enough voltage or current running around to fight
> through the tiniest film of corrosion, so you have to help it along.
> Usually just the plugging and unplugging will make it good for another
> 10 years or so!  On the cards, just pull them up a little and then push
> back down.  A "card puller" tool can be made from a section of
> heavy-duty wire coathanger.  Most all the cards have a couple of 1/8"
> dia holes near the top edge that are spaced about 4" apart...  The
> puller is just a length of wire bent into a "U" shape with the open ends
> bent at right angles for the last 1/4".  Really stubborn cards can be
> pried up carefully by inserting a small screwdriver blade into one of
> those holes and prying GENTLY against the top edge of a shield wall or
> the card edge next to it.
>
> 73, Garey - K4OAH
> Atlanta
>
>
>
> Transmaster wrote:
> > Well the voltages and at the test points are as fallows:
> >
> > Receive:  9.99 VDC on the receive trace, 6 mv on the transmit trace
> > Transmit: 9.99 VDC on the transmit trace and 19.6 mv of the receive
> > trace.
> >
> > Ken
> >
> >
> > On 2/15/07, LeeCraner at aol.com <LeeCraner at aol.com> wrote:
> >> In a message dated 02/15/2007 12:02:44 AM Pacific Standard Time,
> >> ltaft at charter.net writes:
> >>
> >>
> >> At least it has parts that can be seen with the
> >>  naked eye.
> >>
> >>
> >>  After having to repair an SG2020 under a microscope, I can attest to
> >> this
> >> benefit!
> >>
> >>  73
> >>  Lee WB6SSW
> >
> >
>


-- 
Kenneth A. Crips, W7ITC Home of the Chew Crew,  Red Headed
Irish Terrier House Ninjas, Chic', and Cowboy
10th degree black belts in Mouch Fue, Bed Fue, and
Con Artist Fue.