New home-brew 40 meter RF deck

<< < (3/16) > >>

W8ACR:
First of all, thank you to those who replied with offers of help or suggestions. Here is what I came up with. I managed to find a broken but salvageable TVH jack bar in the junk box. After a little epoxy glue, it looks half decent. I also found a swinging link arm and coil that is usable. I was able to home-brew a reasonable facsimile of a 40 TVL coil with PVC pipe and vintage wire. I had to move some things around, so now I have a few empty hole on the chassis, but all in all, I'm happy with how things came out. I do need to figure out how to move the swinging link from the front panel though. Another smoke test is in the offing for Friday.

Jim, thanks for the offer on the parts, but I'll hold off for now in the hopes that this setup will work.

K1JJ:
Cool Old Buzzard set-up, Ron!

One suggestion:  That pi-wound-layered plate choke is prone to arc-overs in high voltage / high power service. They're OK at the 6146 level, but has way too much inductance and inter-turn exposure for high power 40M. Also, potential  inter-turn capacitance problems on 40 M. That choke is probably better for the BC band.  It may work, but is a weak link when the rig is stressed. Replace it with a conventional singe layer plate choke.

They look good, but in QRO, I have blown up every one of those big layered chokes over the years.  

T

W8ACR:
Hi Tom,

Thanks for the suggestion. Yes, I have also fried one or two of the pi wound chokes through the years, and I remember you mentioning this once before. Fortunately, I have two or three homebrew single layer plate chokes available from previous projects. Most likely, I'll pick the one that is self resonant at 40 meters :o

Ron

W8ACR:
OK, a few more changes. I took K1JJ's suggestion and changed the pi wound RF choke for a single layer home-brew choke. I also added a new knob on the front panel that indicates the position of the swinging link coil. I did not try to put it on the air tonight. I'll try to tune it up tomorrow. Pics below.

W8ACR:
Also, a few pics of the home-brew coil construction detail.

Navigation

[0] Message Index

[#] Next page

[*] Previous page