[Boatanchors] HARVEY WELLS TBS 50

[jeremy-ca]

I used a TBS-50D at home and mobile in the 1957-63 era on 80-6M and never 
had it take off.

Rip out any "ham" mods in the RF deck and redo as original. Then at least 
you have a place to start.

Use what photos you can find to get wiring and component placement back to 
original.

A GDO is excellent as a RF sniffer in diode mode.

Modern stabilizing methods would include a 50-100 Ohm 1/2 W carbon resistor 
right at the 807 grid and screen socket terminals with almost zero lead 
length. Plus a 75 Mix or similar ferriteAl value bead between the resistor 
and the wiring for a particularly nasty problem.

Carl
KM1H



----- Original Message ----- 
From: "Gary Schafer" <garyschafer at comcast.net>
To: <k0ewu9 at juno.com>; <boatanchors at mailman.qth.net>
Sent: Monday, March 17, 2008 12:15 PM
Subject: RE: [Boatanchors] HARVEY WELLS TBS 50


> Not quite sure what you are saying? But if you turn the drive way down the
> final could go into self oscillation as there is no screen clamp tube in
> that rig. You can not control the power out with the drive control. You 
> use
> it to set the grid drive to what it is supposed to be after peaking the
> drive and oscillator tune.
>
> 73
> Gary  K4FMX
>
>> -----Original Message-----
>> From: boatanchors-bounces at mailman.qth.net [mailto:boatanchors-
>> bounces at mailman.qth.net] On Behalf Of k0ewu9 at juno.com
>> Sent: Sunday, March 16, 2008 3:47 PM
>> To: boatanchors at mailman.qth.net
>> Subject: [Boatanchors] HARVEY WELLS TBS 50
>>
>> DOES ANY OF THE AUGUST GROUP have much experience with this little beast?
>> I spent a lot of time on one and am puzzeled by some things.
>> with the drive at zero max ,plate current is shown- about 70 mils ,the
>> output is about 40 watts into
>> a 50 ohm dummy load.  Sounds like a parasitic to me?
>> A previous owner had grounded every chassis part to each other with solid
>> wire jumpers
>> using lots of soldering paste flux. (still there)
>> all of the paper caps in the mod section were leaky and were replaced.
>> Could there be a driver/final parasitic involved?
>> HELP!!
>> JACK         K0EWU9 at juno.com
>> _______________________________________________
>
> _______________________________________________
>