Topics

New owner, and impressed!

Dave_G0WBX
 

Hi.

The pre-built Antuino I ordered has arrived, and have to say I'm very
impressed!

Eventually (no info, not even a link printed on a bit of paper was
included, but Google of course is my friend.)  Performed the two needed
calibrations, and it seems to work very well.   Currently using it to
monitor RF levels as I TX WSPR on 40m using the main station rig,
looking for the source of RF leakage!.

The battery tray needed a few minor mod's to take the AA cell's I have
(ALDI own brand.)   I may at some point investigate fitting an ex laptop
battery Lithium cell, and one of the common charger/5V-booster boards. 
That would make a very useful upgrade for me.  (There is enough room in
the case I think if the battery tray is removed, to fit one of the
common USB 5V power bank devices.)

A question:

Does the mixer LO (when working as a "Power Meter") always run on the
High Side, or is there a switch to Low side, at some frequency?  If so,
what frequency..

Other than the Github page*, and the basic info on the Bi-Tx site, is
there any more detailed information available about the project?  Any
simple user manual to download?

* I've pulled the sources, but suspect that they may not be complete.  I
was looking to see where the VSWR "curve" is plotted, to see if I could
flip it, so that 1:1 is at the bottom of the display, not the top (that
is the usual convention in instrumentation.)  If just for ease of
viewing, as that's what I'm used to.

There seems to be a minor issue when scrolling the SPAN frequency
setting too, for the widest span's, more a conflict when a low centre
frequency would result in a -ve  signal frequency value, at wide span's
I suspect.

It's going to take me a while to find my way around the sources, first I
need to find the Arduino toolset for Linux of course.

Overall, a very impressive bit of kit, especially for the cost.

Well done to all involved.

73.

Dave G8KBV. (also G0WBX)


--
Created on and sent from a Unix like PC running and using free and open source software:

 

Hi Dave,

VSWR is from a look up table. I have not played with it.
It will be worth trying to invert the table and see what happens.
I thing its was around line 100 and there was a value of "1" where
it should have been 10 or 11.

It is possible to get better accuracy by using 1/5th of a db from
the A to D than using the Db scale. 1dB = 5 counts.

I say my test units are accurate only swr 1:1 to 1:2

Raj

At 19-10-19, you wrote:


* I've pulled the sources, but suspect that they may not be complete. I
was looking to see where the VSWR "curve" is plotted, to see if I could
flip it, so that 1:1 is at the bottom of the display, not the top (that
is the usual convention in instrumentation.)Â If just for ease of
viewing, as that's what I'm used to.

Dave_G0WBX
 

Hi Raj.

Thanks for the reply, much appreciated.

I'll take another look in the sources soon.  I've now got the Arduino
IDE installed, just have to find my way around it and learn what goes
where etc, before trying anything.   Then, to make sure I can reload the
existing firmware, *when* I mess things up!

I'll report back sometime, when the grey cell has recovered.

73 & thanks again.

Dave G8KBV

On 20/10/2019 12:00, Raj vu2zap wrote:
Hi Dave,

VSWR is from a look up table. I have not played with it.
It will be worth trying to invert the table and see what happens.
I thing its was around line 100 and there was a value of "1" where
it should have been 10 or 11.

It is possible to get better accuracy by using 1/5th of a db from
the A to D than using the Db scale. 1dB = 5 counts.

I say my test units are accurate only swr 1:1 to 1:2

Raj

At 19-10-19, you wrote:


* I've pulled the sources, but suspect that they may not be complete. I
was looking to see where the VSWR "curve" is plotted, to see if I could
flip it, so that 1:1 is at the bottom of the display, not the top (that
is the usual convention in instrumentation.)Â If just for ease of
viewing, as that's what I'm used to.

--
Created on and sent from a Unix like PC running and using free and open source software:

zr6dx@...
 

Hi

My Antuino arrived this week and I was quite excited to get it up and running.  However, after inserting  the 6 AA batteries and switching it on .............dead, no power on the display.  So very disappointing in deed, when purchasing a new unit.    I eventually opened the Antuino, pulled out the old trusty Fluke DVM  and started to trace the power. After a few minutes of checking, I  found that pin 3 of J1 ( External DC power connector) had a dry joint on the component side of the board.  A quick fix with the old Weller and some solder and all sorted. Ashhar thanks for a very useful instrument. Every Ham should have one of these in their shack.

73
Noel
ZR6DX