RadioBanter - View Single Post

April 24th 05, 09:24 PM

In article . com,
wrote:

I will study both pdfs and see if I can come up with a couple of
experiments to see if I understand this.

I am picking up a Pasternak PE2066 DC~6GHz with "N" connectors from
a friend this afternoon.

I have a 1W 7MHz/80Mtr QRP rig that I built to not only be a usefull
CW QRP rig, but it will produce 1W into a 50 Ohm load "for ever". I
have a Boonton "Microwatter" with a 431-4E "head" that is rated down
to 30MHz. I will check it later today to see if it will work down to
7MHz, if not I will have to use my Diawa power meter, lowest scale is
5W FS. I have calibrated attenuators so I should be able to reduce
the 1W to 10mw with no trouble. Iwold preffer to move up to so a
frequency higher and further "in" to the ZFSC-2-1 pand pass, but
unless I can fix a ~5W 6mtr CW rig I put away a lifetime ago I will
have to work at 7MHz. Any errors ought to favor the resitive hybrid.

I wonder if my IC-2AT at low power on 146.00MHz will work very well
for a RF test souce, running from a 9V supply, it ought to be able to
run "key down" on low power for a while before overheating.

Remember to terminate all ports at all times or your results will vary.

The transformer type of splitter will have a "U" shaped response curve
so you need to be within that band for it to work right. The resistive
type is good from DC to some max frequency and you need to be in that
range.

From the transmitter value each output port should be 3 dB down when the
other output port is terminated in 50 ohms. The actual loss will be a
little larger then 3 dB by the splitters insertion loss.

Oh yeah, and your meter is probably a through type instead of a load
type so you need to put a 50 ohm load on the far side of the meter.

When you check each splitter also switch the meter and its load in each
leg to see how balanced the splitter is in each output port.

Be sure to turn the transmitter off before all connections are made or
you could damage your transmitter.

--
Telamon
Ventura, California