I suppose each situation is different. During this contest I tried using a 54
MHz and down low pass filter (between my amp and antenna) when roving but I
took it out as I could not detect it making any difference and I like to
minimize the number of things that can go wrong. Maybe my power amp (and it's
pre amp circuit when I am receiving ?) provides some extra filtering ?
When I first started roving I used to see if I could see any power coming
various down feed lines with a watt meter on it's lowest scale when
transmitting on other bands. I never saw anything. I am also pleasantly
surprised that I have never burnt anything out while roving.
73
Mark S
VE7AFZ
mark@alignedsolutions.com
604 762 4099
> On Jan 18, 2021, at 11:24 AM, Jay RM <w9rm@calmesapartners.com> wrote:
>
> I have the opposite problem. When I TX on 2, it overloads and quiets the
> 6M radio. I have a 2M stub filter on the 6M receive line for other
> purposes, which probably gives me 10-15 dB of extra rejection, but I still
> can't hear anything on 6 when 2 is in TX. Seeing the two antenna are on
> the same mast, separated by 6' and I run high power on both bands, I really
> can't complain. Probably a miracle I haven't smoked something important
> before now.
>
> -W9RM
>
> Keith Morehouse
> via MotoG
>
> On Mon, Jan 18, 2021, 11:40 AM Mark Spencer <mark@alignedsolutions.com>
> wrote:
>
>> Hi Chuck. I have recently started using a filter between my 2M radio and
>> the antenna when I run my 6M and 2M roving antennas on the same mast. It
>> seemed to improve matters considerably.
>>
>> That being said when I usually run separate masts for my 2M and 6M
>> antennas I have little or any interference so my this may or may not be
>> helpful for you.
>>
>>
>> Good luck and 73
>>
>> Mark S
>> VE7AFZ
>>
>> mark@alignedsolutions.com
>> 604 762 4099
>>
>>> On Jan 18, 2021, at 10:10 AM, Chuck Dietz <w5prchuck@gmail.com> wrote:
>>>
>>> I tried dueling CQs for 6M and 2M during the VHF contest. 6m was totally
>>> quiet when 2m was transmitting, but 2m had S9 white noise when 6m was
>>> transmitting. Antennas are 130 feet apart. Happens with even 50 watts on
>>> 6M, although "only" S7 then. Using FT8 for both bands. Rig is Flex 6700
>>> with a DEMI 2m low drive amp with receive preamp. When I transmit SSB on
>>> 6m, it sounds like splattering on voice peaks.
>>>
>>> I need advice on what to try.
>>>
>>> Thanks,
>>> Chuck W5PR
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