Haven't closely followed this thread, but here's a pretty easy to reproduce
splitter, can't imagine the parts costing more than $10, if you're a decent
scrounger even less:
http://wiki.contesting.com/index.php/VP6DX_receiving_antennas#Bandpass_filter-splitter
Julius Fazekas
N2WN
Tennessee Contest Group
http://k4tcg.org/
http://groups.google.com/group/tcg1?hl=en
Tennessee QSO Party
1800z Sunday, September 4 until 0300z Monday, September 5, 2011
http://www.tnqp.org/
Elecraft K2 #4455
Elecraft K3/100 #366
Elecraft K3/100 #1875
--- On Wed, 8/24/11, Jim Brown <jim@audiosystemsgroup.com> wrote:
From: Jim Brown <jim@audiosystemsgroup.com>
Subject: Re: Topband: RF attenuators
To: n4zr@contesting.com, "'TopBand'" <topband@contesting.com>
Date: Wednesday, August 24, 2011, 10:05 AM
On 8/24/2011 3:59 AM, Pete Smith wrote:
> Do you have the capability to measure their response? If they claim
> they are essentially flat down to 5 MHz, and they don't fall off a
> cliff below that, they might be a useful alternative to homebrewing,
> or certainly to the $30 Mini-Circuits splitter.
I have some measurement capability, but with many other things on my
plate, hesitate to repeat work that a very capable guy like Jack has
already done. Although I haven't seen his data, I would certainly trust
it, and would expect it to show degraded response and/or isolation
outside the design range of the product involved, and for lower quality
el-cheapo consumer products. One of the key advantages of the
Mini-Circuits splitters is that they typically offer 20-30dB of
isolation between outputs within their design range.
No, I would not expect response to fall off a cliff at the lower
frequency limit in a Mini-Circuit spec, but rather for performance to
gradually decline at lower frequency. There are a few Mini-Circuits
splitters, that for example, should still work on 160M, albeit with
reduced isolation and/or degraded response. I have a 1x4 that I'm using
to split my Beverages to two main K3 RX and one Sub RX, and a 1x2 that
I'm using to split a 6M preamp to main RX and Sub RX. While I could
split the preamp with a Tee, the splitter provides a lot of isolation,
which has nearly eliminated the strong birdies I used to hear with both
RX running when I used a Tee to split the preamp. I found all of my
splitters at hamfests for a few bucks.
73, Jim K9YC
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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