Hi Larry, It's not necessarily the closeness of the antenna lead that's the problem. Your symptoms point to common mode current coming back on the coax shield to actually be on the chassis of the radi

#raduino #v6

Hi, I would guess that at too low of audio input, you don't have enough drive for the modulator. Instead, once you have a good level for a clean signal, you might want to try adjusting RV1 so the amp

Hi, For best performance, the lm386 should have a bypass capacitor on pin 7. The value is not critical -- any electrolytic from 2-10uF would work. This could easily be added between pin7 and pin4 (gro

#bitx40help #noise

Hi, CHU (Canada) transmits 3 kW signals on 3.33 and 14.67 MHz, and a 5 kW signal on 7.85 MHz.[3] These nonstandard time signal frequencies were chosen to avoid interference from WWV and WWVH. The sign

Hi Scott, For increasing power on the upper bands you should check the Wiki on this group's site. Easy parts for that to get on Mouser or Digikey are the bfr106 and the 2n2222a. I think both are avail

Hi, Concerning the amp. As the finals are MOSFET's (like the IRF510's in the uBitx and WA2EBY amp, etc) they each have different turn-on voltages. This means that there is really no set voltage, even

For your band problem on a v3 or v4 board, These would be the relevent relays/circuit paths to check: /** * Select the properly tx harmonic filters * The four harmonic filters use only three relays *

#ubitxv6 #v6

Hi John, It's typical of finals to have a plateau like that, and driving past that only gains trouble. Not sure how the power tests were done... CW or SSB with tone? SMD transistors are super cheap fr

#ubitxv6 #v6

Hi Jack, I'm not sure it's just you. I remember color schemes most often seen at the beginning of the web and on linux desktops, and I don't ever remember seeing themes so full of low contrast, light

Hmm, Sounds like something was wrong with the board's original mic amp circuit. I can't imagine they are all like that. Good you got it fixed, but it would be interesting to know what the original pro

#bitx20

OK, Here it is with the notes: 73, Mark

#ubitxv6 #v6

Oops, Seems both ended up looking the same. I think the 2nd one just had some notes on the side, but the numbers were the same... 73, Mark

#ubitxv6 #v6

John, Here are PNG versions of VU2ZAP's spreadsheets:

#ubitxv6 #v6

Arv, That's what I was implying. I guess you didn't get it :-( Cheers, Mark

Nah, Just full of passion I think! Lots of way to go about things that's for sure :-) Mark

Or if you want, You can specify an optical encoder instead of a mechanical one. Then all the occasional contact misses will be gone. I think an optical version is only $2 or so more. 73, Mark

Hi, Did you adjust T4, T5, and T6 as described in the manual? Did you try it with an electret microphone first? Have you tried adjusting the mic gain? 73, Mark

#bitx20

Hi again, It's usually pretty easy to tell if a pin got pushed in. As long as the shield cans are all sitting flat against the PCB, then the pins on the other side should all be at the same level. If

Yes for sure, Here is a good article to follow for matching them: http://www.seekic.com/circuit_diagram/Measuring_and_Test_Circuit/Diode_Matching_for_Mixers.html Make sure to handle the diodes with tw

Hi Jason, What capacitors do you have in the filter? It is suggested to use the 33pF value as higher values might not give enough range on the inductors. When the filter is adjusted correctly, normall