Hello - I tried searching the messages here and can't find any info on this:

I am finally was able to start on putting my? early ver 3 ubitx boards into one of Sunil's great looking cases. The case was one of the first ones; I received it in late April of this year. I went to the builder's info on Sunils and ubitx.net and immediately noted that I was missing the Front Panel Socket Board.
I was thinking that maybe the early ones did not have the board included, but the only reference I could find to wiring up the case without the front socket board was some photos he took of the prototype that did not have the board (and included a warning not to try and do it without the board unless one is a advanced builder,? which I am not).
To make sure it was not an add-on to the case package, I also checked all the kits and PCB's on Sunil's www site and didn't see the Front Panel board being sold, so am assuming it should have been shipped with the case.??
I found the N5WLF's excellent "mini manual" that shows the wiring specifics for ver 4 board for those rolling their own cases,? but am not sure if it is usable on ver 3 boards. My other issue is that I am handy with soldering, but go crossed-eyed following schematics - which is why I opted for the ready made case in the first place.??I sent amateur radio kits an inquiry about this but have not heard back. .
If all else fails, I can probably dope out how to put it all together without the "training wheels" , but it will be a struggle. Any ideas or suggestions on how to proceed would be appreciated.?

73,?

John, K7HV

Just checking something,

Woody and Dave, when you do your BFO adjustment, you know you to adjust both the BFO and the tuning of the receiver?? You can't just stay on one exact frequency as you adjust it, you need to fine tune a bit with each move of the BFO freqency to see how clear each setting is.

Another way to adjust it at the start is to do it "by ear".? Just tune to background static only. ? If the background static is low pitched, muffled and hollow sounding, the BFO is set too close to center.? If the background static consists of only very high pitched sounds, then it is too far away.? Aim for something in between to start with.

A really good method is just putting the receiver on a frequency with no signal again, record the background static, then use Audacity to analyze the spectrum. This will show you where the BFO bandwidth is set.? You want it around 300Hz to 2700Hz.

I think the "Spectrogram" program can do this live, instead of having to make a recording each time.

73,


Mark.

Ah you are right I do see that short to ground through the inductor.? ? I can receive signals but they are so low they are almost unintelligible and hard to sound centered on.? Tried the BFO but its as good as it gets on the default.? I tried some different earphones but still no luck? signal either can't be heard or if it can be it's hard to hear.

Tried hooking up a speaker but don't hear anything out of it (have to check if it's hooked up right or drive.)? It sounds to be like there is not enough RF gain perhaps though the noise level is already pretty high so no sure if more gain would make it easier to hear.

I've listened to some folks with their ubitx on youtube and they can send crystal clear and loud enough but mine doesn't seem to have those qualities.? Mostly hard to pick up anything, even on the strongest remote signals not very clear.? Trying with a close radio at 5 watts its a lot louder as expected and clearer but still pretty muddy but intelligible.

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Dave,

Your issues are similar to mine.? Low and distorted audio and lack of RF sensitivity.?? I never fully resolved the situation.? Tried tracing the receive signal with a good scope, but there was too much garbage (no matter where I grounded the probe) to observe changes in the RX signal.? My solution was brute force...?
Audio:? I bypassed the audio PA section and fed the volume pot wiper to an opamp preamp, then to a ~2 watt audio PA chip.? Plenty of not too distorted audio now.
RF:? Built a preamp with attenuator (for AGC).? Used a low noise MMIC for the amp followed by a pin diode (pie) attenuator.? The attenuator works great on a manual control pot.?? Have it working with an audio derived AGC amp now, but that really needs more work since it attacks a bit slowly and has some pumping on very strong signals. I long for one of the old, discontinued Plessey AGC ICs.? I have one in an old homebrew rig and it is great.?

I posted more info on the RF amp / Attn. several days ago...? Subject: ? ?

Good Luck,
Woody



On 12/15/2018 21:31, Dave Space wrote:

Ah you are right I do see that short to ground through the inductor.? ? I can receive signals but they are so low they are almost unintelligible and hard to sound centered on.? Tried the BFO but its as good as it gets on the default.? I tried some different earphones but still no luck? signal either can't be heard or if it can be it's hard to hear.

Tried hooking up a speaker but don't hear anything out of it (have to check if it's hooked up right or drive.)? It sounds to be like there is not enough RF gain perhaps though the noise level is already pretty high so no sure if more gain would make it easier to hear.

I've listened to some folks with their ubitx on youtube and they can send crystal clear and loud enough but mine doesn't seem to have those qualities.? Mostly hard to pick up anything, even on the strongest remote signals not very clear.? Trying with a close radio at 5 watts its a lot louder as expected and clearer but still pretty muddy but intelligible.

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