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[TowerTalk] RCS-4 ant. switch usable on 6 Meters?

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Subject: [TowerTalk] RCS-4 ant. switch usable on 6 Meters?
From: (Jim Idelson)
Date: Wed, 16 Jan 2002 07:17:15 -0500
Hi Mike,

What an opportunity to use your own technical skills. What do you need in the 
way of performance from that switch on 6m? Probably two things: acceptable LOSS 
and acceptable CROSSTALK. I'll bet that with relatively simple equipment, you 
can measure both of these. To measure loss, just put power through it and 
measure. Do this at the power level you plan to use, as the loss vs power curve 
may not be linear. Crosstalk is probably linear - assuming no dielectric 
breakdown - and you can measure that at low power. Apply a strong signal to the 
common and measure the strength of the signal going straight through the 
switch. Now, terminate the straight-thru path with 50 ohms, and measure the 
signal strength with your receiver on the other switch positions. Too much 
leakthrough or not? You decide. Best to do these measurements using the wide 
dynamic range of a level-calibrated sig-gen and operate at the same point on 
your receiver S-meter. The S-meter is notoriously non-linear, so good dB 
measurements over its range are not terribly reliable.

By the time you finish these measurements, Tom will have provided a reliable 
response against which you can can check your results!


Jim K1IR

> Hi All,

Am wondering if anyone knows the cutoff frequency for the RCS-4 remote antenna 

I understand W8JI designed it(?) I sent Tom an Email direct a few days ago but 
no reply, so am going to the group. I saw a very old post on the 'Net (I 
believe by Tom) which eluded to the fact that it may only be good to 30MHz. 

 am building a "K1WA Sloper Array", but for 6m. Is there any problem with this? 
Does anyone out there know firsthand?


7 3 de VE9AA, Mike in snowy NB.......DIT DIT
Michael, Coreen & Corey Smith (VE9AA, VE9AAA & Baby-VE9)
271 Smith Rd Waterville, NB E2V 3V6 Canada 

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