Viking Valiant tune-up question (160 and 80 meters)

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n2awa:
Just finished re-capping, etc. a new (to me) Viking Valiant. This is my first introduction into AM transmitters. I know very little about them compared to most of you!

Tune-up question:

On 160 and 80 meters:
I was finally able to see grid current by increasing the DRIVE control past "3" (owner's manual says to set drive to "3").

For 160 meters, the DRIVE control had to be set at "5".

For 80 meters, the DRIVE control had to be set close to full "10".

Then, when I monitored the plate, I backed off on the DRIVE (a bit) to get 330mA (for phone operation).

Is this normal or does it indicate something is wrong?

WA1GFZ:
You should not reduce drive to reduce plate current. This could mean you don't have a 50 ohm load. The best way is to increase load C. Valients have a common problem of blowing the fixed load caps. An open cap would show up as high plate current and shallow plate dip. Also check your bias voltage on the final grids.
You may be tuned up on a harmonic on 80 meters to require so much drive. Start with the low level stages having the tuning caps at maximum c and tune for the first dip.

n2awa:
Let me back up a step (hopefully for clarity). The first place I see a "problem" when tuning on 80 meters (or 160 meters) is where the manual says:

Turn DRIVE control to 3.

Turn METER switch to "grid", tune EXCITER dial for maximum grid current.

Note that with the DRIVE set to 3, no grid current is seen for any EXCITER dial setting.

Adjust grid current to 8 mA by turning DRIVE control.

Even with the drive set to maximum (10), I cannot attain 8mA grid current.

WBear2GCR:
I have a Valiant II.

Place the thing in VFO position, then over to "ZERO".

First step is to listen for your signal on an 80m receiver - also check 40 and 160.
On my unit, someone had misaligned the "kicker" that switches the VFO off the bandswitch that is found under the unit. It wasn't on 80m when it said it was.

Assumin it is on 80m.

Switch the meter switch to BUFF, and look for a  dip when you move the exciter control. Assuming you see current and a dip, then go to the GRID position you ought to see ample swing.

IF the rig then does not show grid current on 80m, try 40m - that doesn't use the kicker switch! If that works, realign the kicker so that the VFO is on 80m in the 80m bandswitch position... the thing works funny, I had to dork and switch it manually a few times to figure it out.

If that does not work, then see if the rig will load up properly, keep the drive control set to the nominal "3" or "4" position... if the rig loads up properly, then the problem is likely in the metering circuit. If the rig does not load up properly then it's time to scope the drive path...

Hopefully you have a scope to look at what is going on...
A receiver set to the frequency will give you an aural indication of the function of the controls...

               _-_-bear

n2awa:
I can not beat (is that what you mean by "hear"?) any signal on 80 or 160. I guess this makes sense if there is no grid current, then there is no output. But when I go from VFO to ZERO (OSCILLATOR KNOB), the BUFF current does rise a bit.

All of the other bands seemed to tune up into a 50 ohm dummy load (Heathkit "Cantenna") well.

The "kicker" (cam block) may certainly be mis-aligned, as I had to remove it to free up the frozen shaft. I thought I played with enough to get it back on correctly, but who knows.  I can check this again.

Again, when I go from VFO to ZERO, I am seeing NO grid current at any EXCITER knob setting (on 160 and 80 meters).

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