ml wrote:

I agree it is prob 'overload' but thought perhaps notching might
work, i already have some really good multistage tvi filters but
wanted to be ready with a notch for when the building lets me into
the closet in case that is not enough.

My thought was to try and make stubs cause they are 'cheep' but
those links to the commercial site were pretty cool


Stubs work very well. You should try the single wire stub first.

You'll want good low loss coax. The better, the deeper the notch.

1/4 wave for the middle of the 2 meter band, and open at the end should
take out the 2 meter overload.

Anecdotally, I used a single stub during a contest to knock out overload
from 40 meters @ over a kilowatt. The antennas were around 50 feet away
from each other.

- 73 de Mike N3LI -

"Mike Coslo" wrote in message
...
ml wrote:

I agree it is prob 'overload' but thought perhaps notching might
work, i already have some really good multistage tvi filters but
wanted to be ready with a notch for when the building lets me into
the closet in case that is not enough. My thought was to try and
make stubs cause they are 'cheep' but those links to the commercial
site were pretty cool


Stubs work very well. You should try the single wire stub first.

You'll want good low loss coax. The better, the deeper the notch.

1/4 wave for the middle of the 2 meter band, and open at the end should
take out the 2 meter overload.

Anecdotally, I used a single stub during a contest to knock out overload
from 40 meters @ over a kilowatt. The antennas were around 50 feet away
from each other.

- 73 de Mike N3LI -

Being a 2 pole circuit, the stubs are quite broad and because they appear
as a shunt capacity or inductance off frequency can cause major VSWR upset.
The other drawback which may be an issue for TV is that they will also notch
out frequencies at 2N+1 (odd multiples).

Dale W4OP

In article ,
"Dale Parfitt" wrote:

"Mike Coslo" wrote in message
...
ml wrote:

I agree it is prob 'overload' but thought perhaps notching might
work, i already have some really good multistage tvi filters but
wanted to be ready with a notch for when the building lets me into
the closet in case that is not enough. My thought was to try and
make stubs cause they are 'cheep' but those links to the commercial
site were pretty cool


Stubs work very well. You should try the single wire stub first.

You'll want good low loss coax. The better, the deeper the notch.

1/4 wave for the middle of the 2 meter band, and open at the end should
take out the 2 meter overload.

Anecdotally, I used a single stub during a contest to knock out overload
from 40 meters @ over a kilowatt. The antennas were around 50 feet away
from each other.

- 73 de Mike N3LI -

Being a 2 pole circuit, the stubs are quite broad and because they appear
as a shunt capacity or inductance off frequency can cause major VSWR upset.
The other drawback which may be an issue for TV is that they will also notch
out frequencies at 2N+1 (odd multiples).

Dale W4OP

thanks Mike and Dale, hmm so that is a pickle if it notches
out a TV channel hmmm that would be bad the UHF stations would
also be the most week so i guess then i would be sol

perhaps i'd have to use a commercial notch filter then

it's unsure if by coiedence if the harmonics might fall out on a
few of the unused channels or not


hmm

than again i ponder if the digital tv would simply not be
effected by the 10m or 2m rigs, then again could be worse but
perhaps digital tv might actually 'save me''

again i appreciate all those that responded i have a lot of good
ideas to experiement and try


happy new yrs