Date   

Re: manual for v. 3

drichm13@...
 

Thanks Curt. I will try all of these.

David

On Sunday, August 16, 2020, 03:01:58 PM PDT, Curt via groups.io <wb8yyy@...> wrote:


David


Its on hfsignals website. There are links there for v3 v4 etc.

I imagine it may be at ubitx.net, and maybe files section here.

Or use search engine ubitx v3 instructions

73 curt


Re: Antenna problems...

Ken Hansen
 

I encourage your club to consider such a purchase. My local club bought a RigExpert AA-600 to allow us to check repeater sites, and it has become the most popular club asset, loaned out nearly every other week to a member.

Ken, N2VIP

On Aug 17, 2020, at 08:23, Jack, W8TEE via groups.io <jjpurdum=yahoo.com@groups.io> wrote:

If you don't have a VA, perhaps someone in your club does. I think I'm going to recommend a purchase of one for our club...could be useful for our club's FD's, too.


Re: Antenna problems...

Jack, W8TEE
 

Hi Gordon:

Al is a physicist by training, but a really good EE-type, too. He took one look at the plot and said: "That's not right." I nodded like I knew something...Whereupon he immediately did a TDR test using the same VA and that confirm there was a problem. I learn something new everyday...but I'm finding I forget it just about as quickly.

The goods news of this aging problem: I can have my own personal Easter egg hunt!

Jack, W8TEE

On Monday, August 17, 2020, 1:28:35 PM EDT, Gordon Gibby <docvacuumtubes@...> wrote:


What a good pick up. I would never have thought of that.  And to recognize it from looking at a sweep plot is pretty slick


On Aug 17, 2020, at 13:25, Viktors Miske <unclevic7@...> wrote:

Now this is what the hobby is all about! Thank You 

--
Jack, W8TEE


Re: Antenna problems...

Gordon Gibby
 

What a good pick up. I would never have thought of that.  And to recognize it from looking at a sweep plot is pretty slick


On Aug 17, 2020, at 13:25, Viktors Miske <unclevic7@...> wrote:

Now this is what the hobby is all about! Thank You 


Re: Antenna problems...

Viktors Miske
 

Now this is what the hobby is all about! Thank You 


Antenna problems...

Jack, W8TEE
 

All:

Several months ago a Spring storm took my 80-10M EFHW down...again. Last Thursday Al, AC8GY, brought his drone over with its hook attachment and we got the antenna up again, this time higher than before. I made several contacts with it over the weekend and I was a happy camper.

Al came back on Sunday with his VA and did a scan. Since my antenna is identical to his, we should have similar scans. Not so. My resonance points weren't nearly as deep or sharp as his. Because the antenna was new, we started at the gas tube lightning arrestor...looked good. There are two other breaks in the coax to get around obstacles in the house and those looked good. The final link was the shack's antenna switch; a popular brand and not cheap. That was the problem. I had a used switch I picked up for $5 at a hamfest, threw it in place, presto-chango--perfect! Al took the old switch home to see if a cleaning might save it. Turns out that there was some corrosion on the contacts, which raised the resistance to 10Ω. When you run QRP a lot of the time, throwing heat out instead of a signal is no bueno.

As I've said many times before, my domain is mainly software and I would never have noticed this problem and, if I did, I don't have the EE sleuthing skills that Al has. It might be worth checking your system. If you don't have a VA, perhaps someone in your club does. I think I'm going to recommend a purchase of one for our club...could be useful for our club's FD's, too.

Anyway, when I get my current project done, I look forward to getting back on the air again!!

Jack, W8TEE

--
Jack, W8TEE


Re: Assembly instructions for the ubitx v4

Sunil Lakhani
 

Kindly check U1 it is LA4425 with 5 holes on the audio amp board as in picture.
You can buy from aliexpress .
Best of 73s


Re: Assembly instructions for the ubitx v4

Evan Hand
 

Mario,
From the links and your description, I assume that you have an Amatuerradiokits case with the audio amplifier.  If that is correct, then the data that I have shows a TA4225 (not a TA4425) audio amp IC as the audio amp.  That is a 5 terminal device, not 3.  That board is very cramped, so it could be that the silk screening is really pointing out the TA4225 5 pin socket and not the 3 holes that are close by.

Attached are the 2 pdf files that I have for the audio amp.

My guess is that the 3 hole location is for the onboard "volume" control that is really a maximum volume control as the front panel volume control is used to adjust the volume in operation.  You should have a blue 3 terminal variable resistor that goes into that location.

Please verify the above before you start any modifications or soldering.  If you need more help, I would suggest that you post a picture of the board and the location so that we can better help you.

73
Evan
AC9TU


Re: Assembly instructions for the ubitx v4

Mario Koppensteiner
 

Hello Mark,

Am 16.08.2020 04:26, schrieb Mark - N7EKU:
Hi Mario,
Go to the Wiki section of this website, then to uBitx Topics, then
uBitx Assembly. We hide it really well here ;-)
I found this one [1]. The wiring diagram is for ubitx v5. I do own an ubitx v4. What is the difference between the v4 and the v5?

You may also need to do a small fix on the audio amp since I think
most v4's have biasing issues there. Check this post and the
accompanying thread as it covers it well:
https://groups.io/g/BITX20/message/53356
thanks for the info.

Links:
[1] https://groups.io/g/BITX20/wiki/5696

73

Mario Koppensteiner
OE5MKE


Re: Assembly instructions for the ubitx v4

Mario Koppensteiner
 

Hello curt,

Am 16.08.2020 02:16, schrieb Curt via groups.io:
Mario
Hfsignals has builder info, but you have to click the link for
previous versions.
I tried this already.

You didn't say which case, maybe from amateurradiokits.in? see if they
still have info, at one time they also had a website at ubitx.com
Sorry. I bought the 4.3 inch Metal case [1].


Blending rig and case instructions takes some patience. v4 isn't a
follow exact instructions kit, but a homebuild adventure. I suggest
building first with lcd, then later changing displays.
So there is no follow exact instructions guide?

Links:
[1] https://amateurradiokits.in/product/ubitx-nextion-case-for-4-3-inch-display/

[...]

73

Mario Koppensteiner
OE5MKE


Re: Assembly instructions for the ubitx v4

Mario Koppensteiner
 

Hello bitx20 List,

I bought the uBitx Nextion Case for 4.3 Inch Display [1] case.

I got a note that there is the LA4425 transistor missing. I did a internet picture search about this transsistor and found this [2]. This transistor does have 5 terminals. On the PCB there are 3 holes and not 5. Please provide me a picture of the PCB with the LA4425 transistor soldered in.

Can you suggest a source in the internet to get the LA4425 transistor?

Links:
[1] https://amateurradiokits.in/product/ubitx-nextion-case-for-4-3-inch-display/
[2] https://i.ebayimg.com/images/g/s9MAAOSwHnFVxLbm/s-l640.jpg

73

Mario Koppensteiner
OE5MKE

Am 15.08.2020 23:52, schrieb Mario Koppensteiner:

Hello bitx20 list,
I do own an ubitx v4 build kit and an Nextion 4.3 inch Display. In
July I did order a metal case for this transceiver. Now I want to
build this transceiver.
I didn't find the assembly instructions for the ubitx v4. Please
provide me a Link.
thanks
73
Mario Koppensteiner
OE5MKE


Re: Assembly instructions for the ubitx v4

Mario Koppensteiner
 

Hello Viktor,

Am 15.08.2020 23:55, schrieb Viktors Miske:
Mario, give this site a shot;
http://ubitx.net/
I tried this site already.

[...]

73

Mario Koppensteiner
OE5MKE


Re: BITX V6.1 TRANSMIT RECIEVE RELAY SWITCH NOT WORKING IN LSB USB

LAKSH MUTHU
 

DEAR REED,  EVAN, and the group,
       Good day. Thank you very much for your kind helps. Now I have solved the issue and uploaded REED software. The rig is working now.
   Thanks a lot for all guidance from the group and especially Reed and Evan.
Regard and 73
MUTHU
VU2LMN


Re: BITX V6.1 TRANSMIT RECIEVE RELAY SWITCH NOT WORKING IN LSB USB

LAKSH MUTHU
 

Dear All,
    Good Day. In continuation of my above message No. 81273, I am glad to inform the group that the problem has been solved now. I have done the required calibration on the touch screen available in the Settings Menu. After carrying out this, the touch screen started working and the Transmission also works in LSB/USB mode.
    Really UBITX is a wonderful gear to learn a lot.What we have learnt is tiny and what we have yet to learn is to a size even greater than the globe. UBITX and this group  offer good opportunities to learn.
Regards and 73
MUTHU
VU2LMN


kit-projects AGC with uBITX v5 - need help #v5

Rob French (KC4UPR)
 

Hello,

I've posted a few times on here about my kit-projects AGC.  I'm thinking that I've never really had it working right, and am hoping I can get some help.  Here's my setup, and here are my symptoms.

I've got a uBITX v5 with the kit-projects AGC, preceded in the RX path by the kit-projects BCI filter.  I've taken a photo of the AGC board, below.  As I've noted in a previous post, I also have a G4HUP buffer tapped off of the Q12 emitter.  In addition, I've got an audio buffer and preamp for a line out tapped off the VOL-H.  So I can imagine there is some signal loss.  However, that still doesn't (in my mind at least) explain what I'm seeing.

Also, I do have a 1K audio taper pot wired up as an RF gain control.  It appears to work fine, although I always leave it at its max setting (if I decrease it, signal strength decreases appropriately; I just haven't found occasion to use it in practice).  The RF gain pot is wired to the AGC via two lengths of RG-174.  The shields of both are soldered to the pot body, which is grounded to the chassis.  The shields are NOT grounded at the AGC end.  So I think I have installed this properly, though I understand this has been a source of problems for some folks.



The red, green, and blue wires are wired to the switch per the kit-projects instructions, as is the black wire (which is NOT ground, but rather corresponds to the purple wire in the instructions).  I've got a connector that goes to the Raduino A7 ADC for the S-meter, and the yellow wire is the audio input.

I will note that I have no real way to calibrate this thing.  However, I have done a couple of different things to attempt to "force" some AGC action, with no luck.  I will note that I am generally using 40 meter FT8 (7.074 MHz USB) as my "test signal".  There are some very piercing signals, that the AGC doesn't seem to do much of anything with.

Basic Setup:  AGC audio input from VOL-H ("per the instructions")

In this case, I generally see very low signal strengths, even with strong FT8 signals.  The KD8CEC firmware reports ADC values in the range of 20-50 (I understand that this has been divided by 4).  Using my DVM to measure the DC voltage at A7 / the control voltage, it looks to fluctuate between 0.1-0.3 VDC.  As I understand it, this DC voltage is way too low to cause any AGC action.

Next Setup:  AGC audio input from my line out

I have a TL082 configured with one half as a basic buffer, and the other half as a 20dB (100x?) amplifier (reference the TL082 preamp on this page http://rason.org/Projects/opamps/opamps.htm).  I normally adjust the gain control (a trim pot) to provide a reasonable audio level for my sound card--this is actually the whole reason I got the AGC in the first place, to control the audio for digimodes. 

Here's where it gets a little weird.  If I adjust the gain to 0, then the A7 ADC registers about nothing... pretty much what I expect.  However, as I increase it, the control voltage increases above what it was in the "basic" case, but it really never gets above 0.3-0.5 VDC even on those same strong FT8 signals.  Even if I max the gain control on the preamp output.

The strange thing here is that if I max the gain control and run that to my sound card, the sound card at its 0dB gain setting (which is line-level) is completely clipped/flat-topped.  So I would assume this is somewhere around 0.7 Vrms on the audio, which according to the ND6T write-up on the AGC, should yield about 3 VDC on the control voltage... but I'm still only seeing 0.3-0.5 VDC!  And no AGC action that I can discern.

Last Case:  Direct DC control

This initially led me to think that the audio wasn't getting properly amplified by Q1 (the 3904, or whatever it is) in the AGC circuit.  So I tried applying 3 VDC directly to the "Common" pad on the AGC, with the switch in the "Slow" position.  When I do this, I see the expected value on the Raduino ADC (reports ~155, i.e. (1024/4)*(3V/5V)).  However, again there is no apparent AGC action (and in this case, I would have thought it was forced to do it).

So, any thoughts?  What am I missing, or what did I break?

Regards,
-Rob KC4UPR


Re: Sensitivity, Spare-Parts and Quality Questions #ubitx #v6.1 #ubitx

Curt
 

Ulrich

Okay a more careful read I see you have a recent v6. I imagine an email to hfsignals reporting quality issue may get you a replacement pot, otherwise the value and taper should be listed on the parts list.

Many of us modify our ubitx, is the YL a new ham? Nearby hams might help with parts.

Hoping you will soon be pleased with your work.

73 curt


Re: Sensitivity, Spare-Parts and Quality Questions #ubitx #v6.1 #ubitx

Curt
 

Ulrich

the ubitx was certainly designed for the op of humble means, including youth.  perhaps us hobbyists have purchased many of them.  it is an amazing rig overall.  okay we can wonder if 0.1 uV is exaggerated or more likely the designer has excellent hearing (-:  The receiver clearly was designed with dynamic range in mind.  I expect it hears most everything my K2 hears in most bands.  As delivered the principle need is BFO alignment.  

most of our HF receivers from the past several decades likely have similar sensitivity - its other parameters where they separate.  nonetheless I have numerous CW contacts with my ubitx and I am amazed how well it does on SSB (I got fortunate I think in the particular microphone I found in my leftover stash). 

my ubtix v4 was delivered with a potentiometer, but I also purchased an enclosure kit that contained pots and controls.  my unit does not have an of-off switch in the volume control, so I don't recall if the stock volume pot has that feature.  my power switch is a push button in the back - I suggest finding whatever power switch its op will appreciate. 

does the ubitx in your hands have a commercial looking enclosure?  many came from amateurradiokits.in.  Sunil the proprietor would certainly fill you in on the pot, but it might be difficult to source that particular pot in DL. 

okay this list may be biased but the ubitx is a nice radio adventure.  when we have sunspots again, I am imagining lots of folks enjoying it when its their primary rig.  I have plans to set mine up for WSPR reception.  nothing like this anywhere in its price range - but someday watch for the QSX when it emerges (more assembly required). 

73 curt


For Sale: BITX40 - in 3d printed case

WoodJRx@...
 

I have a BitX 40 that I 3d printed a case for, that sits on my shelf unused - I never really used it after wiring it up.  I figured someone here might be interested in it, as radios are meant to be used!  Message me off-list for details, if you're interested.

~Josh
W0ODJ


Re: manual for v. 3

Curt
 

David

Its on hfsignals website. There are links there for v3 v4 etc.

I imagine it may be at ubitx.net, and maybe files section here.

Or use search engine ubitx v3 instructions

73 curt


Re: RE

Lawrence Galea
 

Maybe it will wash the signals from the interference?


On Sun, Aug 16, 2020 at 4:57 PM Viktors Miske <unclevic7@...> wrote:
I'm still trying to figure out how a shower door will improve my ubitx? 

8881 - 8900 of 89309