Hmmmm, what does the heat dissapation look like on the harmonics that the
radios all produce? ;-)
Drake 1Kw Low Pass filter for sale... email direct.
73,
Dave
wa3gin@comcast.net
----- Original Message -----
From: "Frank" <frankkamp@att.net>
To: <fvobbe@wlio.com>
Cc: <towertalk@contesting.com>
Sent: Monday, January 16, 2012 12:20 PM
Subject: Re: [TowerTalk] PL259 Insertion Loss?
> Frederick Vobbe wrote:
>
>>With all due respect, Dan, in design you have to weigh all losses, and
>>one way is not to over-complicate designs with multiple connectors.
>>
>>However, on my station I come out of the rig, to a low-pass filter, then
>>to 4-port coax switch, then up to a Heath antenna switch, finally to the
>>antennas.
>>
>>The dB/loss question came up and we debated it to death in our club,
>>till one enterprising soul suggested we measure the signal levels. A
>>station transmitted a carrier on 7, 15, and 28 mHz, and it was measured
>>in the configuration above, and with a coax from the antenna direct to
>>the rig. We ended up repeating the tests by dropping power to where the
>>signal was barely detectable. The result was; while the loss through
>>the system could be measured, and that measurement was very minimal,
>>from the operator's chair there was no difference between (3) devices &
>>(8) PL259 connectors, and a single RG-8 with (2) PL259 connectors.
>>
>>Now, if you're talking 6-meters and above, (especially 70cm and above),
>>then there is a compelling argument for lessening PL259s in the design.
>>But at that point I would be thinking of LDF50-4 or LDF50-5 with Type-N
>>connectors to mitigate losses.
>>
>>Another critical component is length and quality of line, especially
>>when line is cut and connectors attach with appear reflective. A lot of
>>things weigh in on this issue, but all have to be considered.
>>
>>I'm not discounting losses in PL259s. But I think there is a time to
>>knit-pick, and a time to lean back and operate.
>>
>>
>>Fred/W8HDU
>>_______________________________________________
>>
>>
> Interesting thread. Loss (whatever you might think about its
> significance) can be completely eliminated by doing away with the
> connectors. Just grab some of that 'no-loss' coax I keep hearing about
> and solder it directly into the circuits. No connectors, no loss, no
> problem. Almost as good as mounting the rig on the mast with the rotator.
>
> On a more serious note, has anyone ever tried doing that? Locating the
> rig on the mast next to the antenna and operating remotely? This might
> be easy enough to do with rigs that have detachable front panels.
>
> I am not suggesting that this is a reasonable solution for an HF
> installation but how about UHF.
>
>
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