Intermodulation Performance




No, I have been around, just too busy to keep up with all the threads. I wish there was a “Status” page that could keep everybody posted on progress.




David A Posthuma, WD8PUO


From: <> On Behalf Of ajparent1/KB1GMX
Sent: Wednesday, August 22, 2018 10:25 PM
Subject: Re: [BITX20] Intermodulation Performance



You must have missed the last three months.... and a pair of very long threads!  ;)

To clean that up yes, band pass filters are the option or some very fancy combination of
high pass and low pass which results in the same pass band as a band pass.

Generally the in band spurs happen to be extremely weak and as such not a worry
other than being annoying on receive.


MVS Sarma

 Thanks for nice job. We never get these vertical type relays. The filter caps may be  3  for each section,   so that the user  could reach closer value of capacvcitor by a combination.

On Wed, Aug 22, 2018 at 11:37 PM Warren Allgyer <allgyer@...> wrote:
Hi Kees

I would be honored to test and record data, publish if you wish, any filters you would be willing to send. I would of course return them after testing is complete. If you would like to proceed please contact me privately for shipping info. 

Thank you Kees. 


Warren Allgyer <allgyer@...>


Thank you for the great suggestion. This design is not from me. It is the work of Kees K5BCQ. I agree...... a very nice job and I look forward to testing it.

Warren - WA8TOD


David,  the web page has a wiki...

Maybe the mods could harvest info and post there or borrow from mike at