Topics

uBitx V4 test point measurement chart #ubitx #ubitx-help

Ted
 

Raj, et al,

Might I please get my hands on a list or chart with TP levels, for troubleshooting purposes?   I did a search here on the forum but came up empty.

Thanks,

Ted
K3RTA

Albert Peter
 

In the next few days I will do a setup and troubleshooting section to the user manual, including test voltages throughout the circuit diagram.  We will post a notice when it is ready.

Thanks for asking.

Al

 

Sent from Mail for Windows 10

 

From: Ted via Groups.Io
Sent: Friday, January 11, 2019 5:46 AM
To: BITX20@groups.io
Subject: [BITX20] uBitx V4 test point measurement chart #ubitx #ubitx-help

 

Raj, et al,

Might I please get my hands on a list or chart with TP levels, for troubleshooting purposes?   I did a search here on the forum but came up empty.

Thanks,

Ted
K3RTA

 

 

Ted,

What instruments do you have? uBitx works at low signals, the signal at the product detector is almost
the same as at the antenna. I have been using my spectrum analyser to get the levels.

DC voltage chart is possible.

Raj

At 11/01/2019, you wrote:
Raj, et al,

Might I please get my hands on a list or chart with TP levels, for troubleshooting purposes? I did a search here on the forum but came up empty.

Thanks,

Ted
K3RTA

Dan Schaefer
 

TP list and values would be great. I would like one too if it exists. 
Dan. W3BU




On Jan 11, 2019, at 5:46 AM, Ted via Groups.Io <k3rta@...> wrote:

Raj, et al,

Might I please get my hands on a list or chart with TP levels, for troubleshooting purposes?   I did a search here on the forum but came up empty.

Thanks,

Ted
K3RTA

Albert Peter
 

The test docs will be posted on hamradiodesigns.com in a few days.

Al

 

Sent from Mail for Windows 10

 

From: Dan Schaefer
Sent: Friday, January 11, 2019 7:08 AM
To: BITX20@groups.io
Subject: Re: [BITX20] uBitx V4 test point measurement chart #ubitx #ubitx-help

 

TP list and values would be great. I would like one too if it exists. 

Dan. W3BU

 

 

 


On Jan 11, 2019, at 5:46 AM, Ted via Groups.Io <k3rta@...> wrote:

Raj, et al,

Might I please get my hands on a list or chart with TP levels, for troubleshooting purposes?   I did a search here on the forum but came up empty.

Thanks,

Ted
K3RTA

 

Ted
 

Good day, Raj.

A DC chart would be great.  What I have for diagnostics besides a few good DVM's are a dual-trace oscilloscope, an audio signal tracer, a single tone source, and another HF radio. Back when I worked in a business-radio shop with a proper service monitor, a popular trick was to take a piece of RG-58 from the instrument's RF input and put about a 20mm loop of the inner conductor folded around and back to the shield as a "sniffer". That's what I've done to find the last place the signal appears with any noticeable force at all.  Crude, but effective. Without knowing what I should see at Q90 and beyond, I'm basically just guessing. 

Nothing is obviously burned or exploded except my self-respect at this point!


Thanks,
Ted
K3RTA

Ted
 

Outstanding.  Looking forward to it. Thanks.

-Ted

Sascha Bohnet | DL5SMB
 

There already is a diagnostics guide for V3 by Ufi Auttori, who is a regular here too (at least so I think).
You can download it here uBitx Diagnostics Guide V3

The differences between v3 and v4 aren't so big, so hat this might be of help.

 

Ted,

Just uploaded into files section RC RX/TX voltages without modulation. See files \ VU2ZAP folder.

Power supply adjusted to 12.0V during RX and TX.

Hope it helps!

Cheers
Raj

Ted
 

Hello,

I did some measurements and it looks as if half of my driver transistors are toast, and a few resistors that feed them (actually, the 22-ohm resistors to earth).  As I planned to change them out for metal-can type 2N2222's anyway and drop those resistors accordingly, that will be part of the fix.  We'll see what happens after that.

Thanks so much for the assistance.


-Ted
K3RTA

MVS Sarma
 

Perhaps,  TO18  2n222 has its collector connected to can. we need to be careful while handling times .
 all the best  Ted

 


On Wed, Jan 16, 2019 at 6:56 PM Ted via Groups.Io <k3rta=yahoo.com@groups.io> wrote:
Hello,

I did some measurements and it looks as if half of my driver transistors are toast, and a few resistors that feed them (actually, the 22-ohm resistors to earth).  As I planned to change them out for metal-can type 2N2222's anyway and drop those resistors accordingly, that will be part of the fix.  We'll see what happens after that.

Thanks so much for the assistance.


-Ted
K3RTA

Ted
 

Thank you, sir, and I shall take care.



Be well.


- Ted