[Elecraft] Why Transverters?
Kenneth E. Harker
[email protected]
Wed Aug 7 17:38:00 2002
On Wed, Aug 07, 2002 at 07:34:50PM +0100, Trevor Day wrote:
>
> Anyway, my query is this: I am sorry to say that in order to save some
> time, when I ordered the DEMI 6m transverter, I ordered the ready built
> PCB version. This was to fit into the EC2 enclosure. The DEMI appears
> to have several long, and IMO untidy, above board wire links; largely
> carrying supply volts. Is this normal for this transverter? From an RF
> standpoint I feel quite uncomfortable about this.
> Picture available at:
> http://www.qsl.net/g3zyy
Yes, this is normal. Here is a lo-res photo of the DEMI 144-28CK transverter
inside the chassis DEMI uses. The 50-28CK will be essentially identical
as far as above board wiring goes:
http://www.downeastmicrowave.com/graphics/vhftop.jpg
The reason they do this is that to get the power transistors right up against
the heat sink, the one PCB involved is at the wrong height in the cabinet to
do much in the way of connecting I/O to the board at board height. The
cases seem to be really RF tight, though, so it's unlikely to ever be a
problem.
What is also worth noting is that DEMI uses an RCA jack and plug for 13.8VDC
power in on their transverters. I do not know why they don't use a real
coaxial power jack, especially given that there are other RCA jacks on the
transverter - it seems like the possibility for mistake is unnecessarily
high. When I build my next one, I'm using a standard DC power jack.
--
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Kenneth E. Harker "Vox Clamantis in Deserto" [email protected]
University of Texas at Austin Amateur Radio Callsign: WM5R
Department of the Computer Sciences VP, Central Texas DX & Contest Club
Taylor Hall TAY 2.124 Maintainer of Linux on Laptops
Austin, TX 78712-1188 USA http://www.cs.utexas.edu/users/kharker/
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