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Interesting experiment!? The uBITX receives nicely as is, at least on the bands that are propagating now.? I see it is a beefy, high current amplifier - 2n5109.? It is the same device as used in

Reading down the add, it appears that it is shipped without a clock crystal as well. Woody, KZ4AK --

For "short distance point to point data exchange", here's an interesting 100mW 434mhz transceiver: ? ??https://www.sparkfun.com/products/13910? That sort of thing is also available for the 915mhz

I have purchased using PayPal a couple of times [email protected]> wrote:

You didn't select free shipping! Roy WA0YMH

I am having trouble buying the above from India (HFsigs website). My debit card was not accepted. I paid with a credit card which seemed to be. When I had entered my details I got a message saying

Well, yes. But then the shipping is $2.50? Not such a good deal anymore.

Appropriate FET's can switch low level RF. But it's usually PIN diodes or relays when switching power at the output of a transmitter. Google "1n4007 as pin diode TR switch" for ideas on how it gets

This is k0mbt looking for a bitx > bitx qso. 73 Dave

The reason FM isn't used has been pointed out. The lack of band to use and the loss of efficiency mean HF and FM just aren't compatible. Bands like 2 meters or 440 have more bandwidth. Sure FM sounds

All gravy, I made my on PCB smd. PCB looks gorgeous. Will send a pic. Having breakfast presently From Andrew

Thanks again everyone for your input. The goal is to experiment with digital for short distance point to point data exchange. Just a fun challenge to take on and learn in the process. I now see that

Have used MOSFETS to switch high current, low voltage lines.? Some of the newer devices offer on resistance of just a couple of milli-ohms.?? A TO-220 can switch well over 20 amps even with no heat

Agree...?? But I have used PIN diode switching.?? Lot more complicated than relays and often a bit lossy, but neat ;) Woody ---------------------------- --

Exactly

Lots of 2m FM repeaters out this way. A Baofeng handheld is $30, but if you want to homebrew then have at it. Would take some major surgery to turn a uBitx into an FM rig. And even more to have it

Clarifying my question, the scratchiness is between characters, NOT T/R transitions. Otherwise, AGC mod works FB! Any ideas John K5MO

Please explain with a schematic, hand written might be fine as well.

I had one amazing contact on 10m. I suspect it was gray line propagation. Im pretty sure it was ssb and I worked Tampa Florida to Australia. I agree with the doubt that FM is worthless to dx because

Hi, Opto takes a logic signal and is isolated from rf power. Fet switch's rf. Opto takes input voltage from 2v up to 50 volts sharp pc817. I'm only using relays these days for high current