开云体育

Hmmm, I'm not assuming anything about drain loads, only that the load on the output of the transformer should be 50 ohms. The LPF's on the uBitx and WA2EBY are symetrical, 50 ohms in and out, no

Very good, Jerry. However, note that the output is NOT 50 ohms until AFTER the LPF. The input to the LPF is somewhat lower. And the WA2EBY has a voltage advantage over the 12V input to the drains,

He might be referring to the MRFE6VP61K25H/HS. Probably seen here: http://www.eham.net/ehamforum/smf/index.php?topic=75793.0 Vince. -- Michigan VHF Corp. http://www.nobucks.net/

Impressive. But what's an SER? When I google "transistor SER" all I get is a bunch of Spanish language pages.

I've now uploaded an LTSpice simulation schematic file that allows easy comparison of the uBitx and WA2EBY finals, also a pdf version for those who have not installed LTSpice: ?

Bill:? Sometime ago I read about a transistor that can handle a 65:1 SER. Do you know anything about the device? Sent from my Verizon, Samsung Galaxy smartphone

Ha! Re-designing the transformers is most of the tricky work. Yes; you will have to do that. It might require some experimentation. Try to use FT-61 hog-nose material. I think it will be more or less

Excellent, thats what I am hoping to get to. So the bias will need re-adjusting... Easy....? What about the input and output transformers? I assume this will need modification due to the differnet

See attached? diagram I use for connecting the Colour TFT and atmega to the UBITX Joe VE1BWV

Two RD16HHF1 parts replacing the 510’s will do that. Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ Owner - Operator Big Signal Ranch – K9ZC Staunton,

Cesar, When I get back to town and my bench I will check and tell you. Raj

Or a Youkits TJ5A

I just wanna be able to output 5-10w on 28mhz.... not 1w... My QTH is pretty remote and without "decent" power, I wont get any contacts on >7mhz... Might have to seriously consider an FT817, but the

Did you re-bias the 510s when you changed the PA voltage? If not, theoretically this could happen if the bias were set right on the edge of class “C” operation. Dr. William J. Schmidt -

Somebody already did the amp for you: ? ??http://w6pql.com/1_kw_sspa_for_1_8-54_mhz.htm#rfdeck Unfortunately, it requires 2 or 3 watts going in for full output. So we still have to bring the uBitx

Yes it does, I never would have figured that out! I wanted to include that appropriate CAL value in my version of your sketch to pretty much get it calibrated correctly when restored to those

Touching back on this, it's feld-hell's lower duty cycle that was causing the lower current draw. -- ---------- N5WLF, Greggory (or my nickname, Ghericoan) General Class, Digital Radio Hobbyist

Check this socket trick below that someone else posted. Then fold the RD device over and screw it to the case. Tab is not hot any more. Re-bias. Dr. William J. Schmidt - K9HZ J68HZ 8P6HK

RoboDyn is a good outfit...even though they have little to do with the Arduino outfit. Ought to work well if you get a genuine RoboDyn unit. It has a CH340 interface and micro B USB connector and is

Well, it's nice. But you still have to design the amp. And blowing up one of them is a whole lot more expensive. Hi. Let's see...I could get about 42 RD16HXXX devices for every one of these. And if