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Thanks, Ian.? Got it.? Eddie

Terry, You need a separate band pass filter for each band if you want to use the single conversion BitX40. The UbitX uses double conversion that eliminates that requirement. You could use a multiple

A search within yahoo groups and groups.io for "antennas" finds dozens of such groups. Also also some in the www.arrl.org forum, and forums.qrz.com forums, among others. Some with one or two members.

Mike, You solved the source issue.... with the counterpoise as suggested I did say the SWR will likely change. Generally the 1:9 scheme is problematic for RF in the shack unless you have luck or

This is primarily an SSB transceiver, and harmonic suppression seems adequate in that mode on the stock rig.? Best and easiest fix is probably to either not use CW mode, or do a minor hack to move

Iz oos, TLTs can be made with low loss.? ? However making a matched set may be harder as they have to have the exact same phase response. Also the 1:9 is 450 ohms? (50*9). Allison

Make sure you have adjusted the BFO to the correct frequency.? The carrier will drop. Allison

Allison Have you shared your past findings here? I did a search and found nothing but I could have missed it. It would seem to me that if you knew the product was illegal for use on the air you would

Warren, Latching relays have a higher cost, I like the idea though.? However there are lower power relays that would do the job.? Since the radio eats power on TX anyway another 200ma is tolerable.

Arv, For bitx20 (or 40) a monoband radio traps and Caur filters are a good solution. For a multi band radio its a spot solution that is likely to case troubles on other bands. The fundamental issue

Warren, In my testing I also found the isolation across one relay was barely 45db in one configuration and 50 in another. Using one relay to switch both ends of a filter will compromise the filter

I am not sure Arv. The real solution here is like a "fork lift" upgrade, replacing everything after T11 in the transmit chain. If I were doing a redesign I would use the same four filters, add five

Warren WA8TOD That is interesting, and a bit disturbing as well. What might be the effect of adding a series LC trap to ground at the antenna end of the filter, or maybe at the RF PA end of the

BTW..... in re-reading this, unfortunately after it was posted, I note that my threshold line is set at -53 dBc rather than -43. In your imagination move the green line up one division. It does not

No one is going to want to hear this but the design of the PA output filter is probably fatally flawed and it is likely due to board layout issues. I have been puzzled how the high order harmonics of

Check my website, www.w0eb.com ( http://www.w0eb.com ) for details, but I now have a completely drop-in Raduino clone available in kit form for anyone needing a replacement for a damaged Raduino that

Hi! Has anyone one tried MEMS microphone like these.. https://www.adafruit.com/product/2716 Replacement elements for mobile phones are available quite cheap. Some variants come with in built

Hi all. I don't know how to suppres great carrier in TX mode.

Allison, Here paralleling of cap arose? due to sheer unavailability of good quality caps in pF range in local mkt. I wanted to optimise the filters to best possible extent on local components so that

Hi Eddie, wiring for 4 pin : pin 1. Mic input, pin2 PTT,pin3 is put ground and pin 4 is mic ground. So link 3and 4 to earth and pin one is mic and pin 2 is ptt makes sense to keep connections short