Item is sold. ?Thanks for all your interest.
Howard

This is the first I have heard of this issue on the uBITX. ?

There was a similar issue with the BITX40 and?Allard, PE1NWL implemented a code workaround to suppress it by temporarily shutting down the Si5351 CL2 for about 50ms after PTT closure,?to let things settle down before allowing the rig into TX.?

Michael VE3WMB?

Noise level is 20 over 9 here tonight. It's even really noisy on 6 meters, which is unusual.?
--
John - WA2FZW

I can still hear you calling, John WA2FZW but you don't seem to be hearing anybody..I'll keep trying. Working N4DR Marc in Maryland, WA4THR Vic in PA and WA3O Mike in PA.so far. Can also hr TN so lets go hihi

开云体育

The digital synthesizer doing something as it settles on frequency?

Who knew they are called Vactrols? Anyway found them for $1.99 here.

Joel
N6ALT

Hi Warren,

Thanks for the reply. I noticed that it occurs on all bands and that the spurious output is always in the same relationship to the operating frequency so I suspect that it is not because of the PA itself going into oscillation as that would certainly be band specific. It seems that if it is a problem common to all bands and frequencies, it could be due to something with one of the local oscillators. I wonder if it is something to do with the firmware or timing issues? I'm sure someone will come up with a solution!
73,
Bob N1KW

John...hang in there...I can hear you well up here! They are coming out of the woodwork so its a free for all.?
Tom VE3THR

Yes, we usually have both VE3THR and WA4THR on the net!
--
John - WA2FZW

Oh well, Not getting any answers even with the TX power cranked up to 100W. See y'all next week (I hope)!
--
John - WA2FZW

You mentioned VE3THR in your last post, the one I'm hearing I could swear he gave his call as WA4THR. An N4 something (N4DR?) is coming in at an S8 but his audio is a bit muddy and I couldn't make out the rest of his call, he's talking to WA4THR and someone else.

Vince - K8ZW.

--
Michigan VHF Corp.

On Sun, Jul 29, 2018 at 07:14 PM, Vince Vielhaber wrote:

I'm hearing you, John, in Oxford, MI

Well, that's good news! I thought I didn't have an antenna tonight also. 40 meter loop didn't want to tune. Fortunately the problem was?only that the control cable pulled out of the back of the control box.
?
--
John - WA2FZW

I'm hearing you, John, in Oxford, MI. Don't have a working 40 M antenna tho.

I'm hearing a couple of other stations too. Someone is currently using a Bitx40, doesnt yet have a uB. I think he has a 4 call.

Vince - K8ZW.

--
Michigan VHF Corp.

I hear Tom (VE3THR) talking to someone that I can barely hear. Tom's signal is up and down. Lots of QRN here tonight.
--
John - WA2FZW

Peter,

First ditch the 3904s or the similar parts used are near dead at 6M and forget 2M as the layout
is unfriendly to VHF there.? ?

You will need a bandpass filter at 50Mhz.? A dds generally doesn't reach high enough without spurs
(9850 and 51 are not much).? You will need about 5mW of RF any way to drive the DBM.? The?
one you pointed at using aa 5351 is a good start, mod the code and it can go much higher.

The only part in the transmit amp that will work at 50 mhz is the IRF510!? You have to drive it just
like any other RF mosfet (RD, BLF, MRF) as the input impedance there is rather low.? At 13V
it can do 5-7W and the power gain is in the 10-13db region.? ? Everything before it has to be
redone and the minimum is 2n5179, 2n3866 types.? ?If the RX fist stage devices are decent
at 50mhz (BFR106 or that sort) the RX should be OK, a bit noisy for weak signal work but
a start.? I've used 2n2222a at 50mhz and gotten about 250mW out of them and about
10db of power gain.? It takes a bit of coaxing.? For 50mhz there are a lot of CATV
transistors that can do 1-2W so look for those.

Changing sideband is only matter of a coil or capacitor to move the BFO rock as needed.

?Other than a simple low pass filter (7th order) and a decent bandpass filter the biggest issue is
most of the BJT semiconductors used have a FT of maybe 300mhz and at 50mhz the gain
will be very poor.? So just replace them as a matter of course.

For 2M move to 10M, dump most of the TX rf and use a transverter.? Most transverters
only need a few milliwatts at most for drive.

FYI I tried it for 6M about 11 years ago with the original bitx20.

Allison

We've had some discussion about moving the uBitx up into VHF.
Conclusion seemed to be that the best bet would be to run it at 30mhz and use one of the Ukranian transverters.

The FM thing came up then, in regard to the uBitx.
To get that going would require replacing the other half of your Bitx40,?
so about all you are left with is the audio.

The old analog VFO would definitely not be stable enough,
and possible the si5351 on the Raduino might be noticibly shaky up there as well.

I have seen the same thing Bob on the spectrum analyzer. A big burst of wideband energy on the initial character. Mine does it from time to time upon PTT initiation.?

I only got got mine running a couple of days before vacation and am planning to dig into it further this week when I get back to the lab.?

It has has all the symptoms of the PAs going briefly into oscillation.?

WA8TOD

Jerry...In my email client I set up a folder for the BITX20 group. I then added a filter to route anything with 'BITX20' in the subject to that folder. Keeps the main inbox less cluttered and makes it easier to see all the BITX20 stuff in one place. I use the Thunderbird email client but I think most of the others have a similar capability.?

Mark? ?AA7TA

Go to QRPKITS.COM and you can find manuals for both BitX20 & 17.?