Thanks Ed for letting me know the plate voltage. I have been using it with
a Heath PS23 and using the low voltage feed and as it turns out it is 250vdc
but it is good to veryify that was the designed B+.

I have looked through a quite a few handbooks and a Google search but no
luck finding anything like this yet. So will keep pluging.

It does have a few problems......1.) The tuned output from the buffer does
not respond on 80 meters like it should. I can not get the coil to resonate
like it should on 80 but it works fine on 40......2.) The antenna loading
tuning capacitor has no effect at all...just like it is not there or
something but it is wired in and not shorted...So this has me stumped...The
plate loading cap works but when rotating it I get a peak in the power
output but no dip in the plate current...How can this be???

I did find a bad tube socket in the oscillator (12AU7) and have replaced
that now and it doesn't get intermmitant any more so there is some progress.
Any ideas from anyone as to why the Antenna Load Control has no effect and
how I can get a peak in power output with a dip in the plate current??

Steve NU0P


"Edward Knobloch" wrote in message
news:FxKcf.8566$SV1.1636@trndny01...
Hi, Steve

You're right, the QST article has no schematic.
I just thought the review would be interesting reading for you.

The rig requires 6 or 12V for the heaters,
and 250VDC for the plate supply.
The 6AQ5 modulator is designed for a carbon mic.

Ed

Steve NU0P wrote:
Ed

Thanks for the information but unfortunately my library of QST goes back
to 1990 only, will have to ask around to see if anyone has that but as I
recall QST did not publish any schematics usually.

Steve


"Edward Knobloch" wrote in message
news:OMtcf.23445$w_6.17319@trndny09...

Hi,
The Mars Thunderbird was reviewed in March 1960 QST.

73,
Ed Knobloch