Indeed. Too many people take the "maximum specified loss" or "maximum
mismatch" in the data sheet as the value, when in reality, those numbers are
more "that's what we can easily measure, with measurement uncertainty, on an
assembly line".
that 1.03:1 VSWR that shows up in lots of connector specs - that's as low as
you can measure without going to herculean efforts. Remember that if your
power meter has 0.1 dB uncertainty, and you measure zero loss, you could have
up to 0.1 dB (or, equally, you could have 0.1 dB gain! :) ) More than one
person has been bit by not accounting for measurement uncertainty when setting
pass/fail levels.
On Sat, 23 Aug 2025 15:39:58 +0000 (UTC), Wes Stewart via TowerTalk
<towertalk@contesting.com> wrote:
Well, I'll fix that. Connector losses are usually overestimated. If they are
well mated, loss is difficult to even measure. But what they introduce is
unreliability. Type N connectors are, in my experience, unreliable when
outside with the temperature extremes here in the desert.
On Saturday, August 23, 2025 at 07:45:48 AM MST, Mike Fatchett W0MU wrote:
The silence is deafening.
On 8/23/2025 8:33 AM, Chuck Dietz wrote:
> I have been thinking about this myself and I wonder if the connector
> between the hardline and the rotor loop might have more loss than the
> difference between the hardline and LMR400 ultra flex cable. In other
> words, maybe just run LMR400 and not have a connector in line.
> I have not done the math, but I think it would depend upon the total length
> of the cable. Mine will go from the stackmatch to the bottom of the tower
> where it will connect to 7/8” hardline.
>
> Chuck W5PR
>
> On Sat, Aug 23, 2025 at 9:09 AM Jim Miller wrote:
>
>> 6m beam. i have a rotator loop. this is for the longish boom run.
>>
>> i've got it all figured out so now to implement.
>>
>> i had no idea that ferrite beads over 1/2" hardline would be so
>> controversial.
>>
>> jim ab3cv
>>
>> On Sat, Aug 23, 2025 at 8:58 AM Chuck Dietz wrote:
>>
>>> Jim, is this for a fixed antenna or a rotating tower? Or, is it for a
>>> rotator loop?
>>>
>>> Chuck W5PR
>>>
>>> On Fri, Aug 22, 2025 at 5:44 PM Jim Miller wrote:
>>>
>>>> I found some. In stock. No problem.
>>>>
>>>> Jim ab3cv
>>>>
>>>> On Thu, Aug 21, 2025 at 4:54 PM Jim Miller wrote:
>>>>
>>>>> I'm redoing my 6m feed along the boom with LDF4-50 and would like to
>>>> put a
>>>>> string of type 43 cores along it.
>>>>>
>>>>> Has anyone here done that and what did you find to use? I'd like to
>>>> avoid
>>>>> including a normal piece of coax if possible.
>>>>>
>>>>> Thanks
>>>>>
>>>>> Jim ab3cv
>>>>>
>>>> _______________________________________________
>>>>
>>>>
>>>>
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>>>>
> _______________________________________________
>
>
>
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