[ardf] Transmitters and Fox Boxes...
sam.smith at ece.gatech.edu
Thu Aug 14 15:01:34 CDT 2003
Matthew Robbins wrote:
> 1. Do you use bulkhead connectors for piercing the ammo can, or just
> RTV the coax in a hole, or something else?
bulkhead connectors for the 2 meter, binding posts for the 80 meter.
> 2. Do you use different connectors (e.g., BNC, SO-259) for the 2m
> and 80m antennas? Where do you have disconnects? I was thinking
> soldered coax at the 80m TX, BNC at the HT, and then disconnects at the
> box bulkhead, inside and out, and then soldered joints the rest of the way.
different connectors. I never disconnect anything inside the box except
the battery. Everything else is soldered with strain relief except for
the BNC connection to the HT.
> 3. For 80m do you use coax or twinlead from the box to the antenna
> (e.g., SO-259 or binder posts).
From the binding posts just short lengths of wire straight to the
antenna and ground radials. It's only a few inches.
> 4. Do you have a way to measure and adjust SWR in the box, or do you
> do that at home and assume everything is the same at the transmitter site?
Adjust SWR at home and don't worry in the field. I did adjust radials at
the US Champs on 80 meters for lowest SWR but not usually.
> 5. If you use HTs for control of an 80m transmitter, what kind of
> antenna do you use for the 2m link? (Probably not a turnstile?)
The same turnstile that I use for the 2 meter transmitter.
> 6. Do you try to eliminate the ON7YD oscillator noise on 80m? How?
Yes, I have a little circuit that turns on the oscillator whenever the
key line is active. It's an RC delay of a few seconds, so it stays
active during the CW and turns off the oscillator a few seconds after it
> 7. Have you had any trouble with RF on feedlines or power cables?
> Do you use Ferrite or loops of the cable/coax (common-mode chokes)?
No, I don't use anything.
> 8. Did you try to keep the CG underneath the handle? It seems like
> you have to put the battery in the middle of the ammo can to make it
> balance right.
Batteries are in a back corner, at the bottom, wedged in with foam.
> 9. How do you select 80m or 2m or both? Switches? Solder? Change
> plugs at the Controller? (Can a Pic-Con do both at the same time?)
> (For PicCon users with remote control: How do you switch off or
> otherwise disconnect the 80m TX when set up for 2m?)
I have a switch that changes? something, I forget what. I don't want the
2 meter transmitting at the same time. Actually I can still control the
80 meter transmitter when it is transmitting, which is sort of cool.
There is also a command to the piccon that changes the CW control line
to real CW. (B502? B500?)
> Today I went to three different stores looking for ammo cans. (One
> place advertised 50cal boxes for $2.99.) They were all out. *sigh*
> Well, Tomorrow is another day.
One of my boxes is the smaller ammo can with a 5ah battery. Works just
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