开云体育

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

Hi Allison, these 1:49 transformers are just conventional transformers. Would you think that a 1:4 and a 1:9 current (not the voltage ones) transmission line transformers in series to get a ratio 1:36

Again, thanks for the explanation.? After adding the air choke and counterpoise (17.5ft -- I'll trim it back tomorrow), *the uBITX now behaves properly when keying the mic and transmitting CW!!!* The

No it wasn't. Arv just created the antenna group today. The loop group you're talking about is different. Vince. -- Michigan VHF Corp. http://www.nobucks.net/ http://www.CDupe.com/

formerly it was https://groups.yahoo.com/neo/groups/loopantennas/info Regards MVS Sarma vu3zmv

antennas /g/antennas Vince. -- Michigan VHF Corp. http://www.nobucks.net/ http://www.CDupe.com/ http://www.metalworkingfun.com

Yahoo group "loop antennas" moved here /g/loopantennas Regards MVS Sarma

If one has working MICs meant for other rigs that he uses, we can by a similar connector and wire accordingly . It helps sharing the same mic for ubitx. regards sarma vu3zmv

What is the exact name of the new antennas group that has been mentioned here? Al, KB4RA

There really is no "standard" for wiring mic connectors. Each brand seems to have their own scheme. Unless you are trying to match a mic from an existing radio, just wire it so it makes sense to you.

Al Peter, AC8GY, who has a lot more assembly skill than I do, made this mic for me using the stock element and switch: The case is one of those promo pens that had a small LED and battery in it. It