Date   
Re: Spectrum analyzer fun

 

is it too soon to share the fix?
--
David

 N8DAH
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Re: Spectrum analyzer fun

Laurence Oberman
 

Awesome,
While I am an extra I would love a recording of that class as it will
have years of experience included :)
I did spend a bunch of money recently to take the Besser Associates RF
technology class to give myself a full refresh of all things RF.

Make me wish I had stayed in RF years ago instead of software.

Nice job Sir

Regards
Laurence

On Thu, Jul 25, 2019 at 4:41 AM Gordon Gibby <ggibby@...> wrote:

Oh what fun!

Yesterday I built a simple capacitively coupled "probe" to be used with my (1st ever!) spectrum analyzer. A series cap of 0.01/1kV, 4700 ohm resistor, and 100 ohm to ground, (should have used 50 but didn't have it) -- then coax cable to the spectrum analyzer.


Gives roughly 15 dB attenuation based on touching the tracking generator signal.


Allows me to actually SEE the oscillators and signals as I roam around the uBix. Wow, the signals are TINY all around the receiver, and most of the gain must be in the audio section....


I built this for 2 reasons: primarilly so I can do this demo for our upcoming Extra Class course, and let people SEE mixers in action and oscillators and filters. Sending in a 100kHz calibrator (harmonics every 100 kHz) shows ALL the signals heading into the 45 MHz filter --- and then poof, only 1 left afterwards!


2nd, I have a heathkit SB-102 with local oscillator problems and this will help.

Fascinating.


Gordon Gibby KX4Z




Re: Support bracket for Raduino / uBitx

Wayne Leake
 

 Looks very good, aside from the right side being specific for your case.
 I plan to mount my Raduino directly to the front panel, as I'm using a couple of different cases,
 and BITX40's and one BITX20 (when I get it assembled.
 I hope others will make good use of your work.
 I know it takes time and effort.
 Wayne WA2YNE


Re: Squelch Control??

Lawrence Galea
 

On Thu, Jul 25, 2019 at 3:05 PM Tom, wb6b <wb6b@...> wrote:
On Wed, Jul 24, 2019 at 02:40 AM, Gordon Gibby wrote:
Thank you for that real-world input!   May I ask what band your group uses?
Hi Gordon,

We have a net on the weekend at 8 am pacific time on 75 meters. At that time of the day we have good coverage to our local group (in Southern California) as well as few additional hams in Arizona and Northern California. Throughout the day the 75 meter band generally works well for our local members. 

75 meters has a fairly high background noise level here, none the less it has the right coverage for local and a few folks farther out.

Tom, wb6b

Re: Squelch Control??

Gordon Gibby
 

Thank you for the information. I’ve toyed with trying to start a county net on 75 meters 


On Jul 26, 2019, at 05:03, Lawrence Galea <9h1avlaw@...> wrote:


On Thu, Jul 25, 2019 at 3:05 PM Tom, wb6b <wb6b@...> wrote:
On Wed, Jul 24, 2019 at 02:40 AM, Gordon Gibby wrote:
Thank you for that real-world input!   May I ask what band your group uses?
Hi Gordon,

We have a net on the weekend at 8 am pacific time on 75 meters. At that time of the day we have good coverage to our local group (in Southern California) as well as few additional hams in Arizona and Northern California. Throughout the day the 75 meter band generally works well for our local members. 

75 meters has a fairly high background noise level here, none the less it has the right coverage for local and a few folks farther out.

Tom, wb6b

Re: Squelch Control??

Tom, wb6b
 

On Fri, Jul 26, 2019 at 03:54 AM, Gordon Gibby wrote:
Thank you for the information. I’ve toyed with trying to start a county net on 75 meters 
Since I mainly get on 75 for the local net, I've found a compromise antenna of 53 ft works well enough to hear and be heard by everyone on the net. It is good that hams wanting to be a part of a 75 meter net can do so without needing the room for a full sized antenna. A month ago, net control was managed portable from a local air show we had a booth at. Our net control operator managed to run the net with a short loaded dipole antenna. I think someone had to relay for one station, that day.

Before I bought the used Kenwood, I would check into the net with the uBitx. The AZ station had difficulty hearing me with only 10 watts. At times everyone heard me on the uBitx. The uBitx was one of the radios that got me back on the air after a fairly long absence. 

Here is a description of the antenna I use. I bough their toroid kit (and a toroid for a common mode choke on the coax), hand wound the transformer and mounted it in a PVC conduit right angle coupler box from the local hardware store.
 
https://palomar-engineers.com/wp-content/uploads/End-Fed-Antenna-Secrets-San-Diego-hamfest-10062018-Update.pdf

Tom, wb6b

Re: Squelch Control??

Gordon Gibby
 

Thanks for that presentation, I went through it it was excellent.   I think our club is still going to do a resonsnt end Fed project


On Jul 26, 2019, at 10:30, Tom, wb6b <wb6b@...> wrote:

On Fri, Jul 26, 2019 at 03:54 AM, Gordon Gibby wrote:
Thank you for the information. I’ve toyed with trying to start a county net on 75 meters 
Since I mainly get on 75 for the local net, I've found a compromise antenna of 53 ft works well enough to hear and be heard by everyone on the net. It is good that hams wanting to be a part of a 75 meter net can do so without needing the room for a full sized antenna. A month ago, net control was managed portable from a local air show we had a booth at. Our net control operator managed to run the net with a short loaded dipole antenna. I think someone had to relay for one station, that day.

Before I bought the used Kenwood, I would check into the net with the uBitx. The AZ station had difficulty hearing me with only 10 watts. At times everyone heard me on the uBitx. The uBitx was one of the radios that got me back on the air after a fairly long absence. 

Here is a description of the antenna I use. I bough their toroid kit (and a toroid for a common mode choke on the coax), hand wound the transformer and mounted it in a PVC conduit right angle coupler box from the local hardware store.
 
https://palomar-engineers.com/wp-content/uploads/End-Fed-Antenna-Secrets-San-Diego-hamfest-10062018-Update.pdf

Tom, wb6b

#Antuino: an update and a bit of bad news for those bought it at FDIM-2019

Ashhar Farhan
 

Peeps,
The Antuino has been in use for over a few months now. We had produced 100 of them that were sold at the FDIM. These work quite well for an SWR meter and Antenna Analyzer, but they were sub-optimal for serious RF work. For those who bought it for SWR measurements, you can continue to use it. For those who want to improve it, read on.

It was noticed that the db scale was not accurate. Antuino was designed to be an accurate and precise instrument. The db readings should be within +/- 1 db accuracy. However, they tended to vary by as much as 2 db on the upper range of power measurments. This was finally tracked down to having too much gain. I had prototyped the original with 2N3904 transistors but in production we used BFR93W as I guessed it would have 'better' performance. It turned to be a bad choice. The higher gain resulted in compression of signals above -30 dbm. This restricted the useful range of the Antuino to about 50 db. 

I am attaching the new (Version 2.1, it is a minor edit of the V2 that was sold at the FDIM). In summary, these are the changes:
1. The new software with a cleaner way to calibrate is on https://github.com/afarhan/antuinov2.1. Please upgrade to it even if you don't want to carry out the other hardware modifications.
2. Replace the Q1 and Q3 transistors to 2N3904. Although the PCB pads are SMT, you can solder the leaded type by twisting the legs around.
3. In the first IF amplifier (that immediately follows the mixer), we decrease the emitter resistor (R18) from 100 ohms to 51 ohms (you can also parallel a regular 1/4 watt 100 ohms with the original 100 ohms to get to 51 ohms). We also parallel the (R19) 220 ohms collector load with a 10 uh inductor (you can use 10 turns on FT 37-43), the exact value is not important.
4. In the second and third IF amplifiers, we replace the 100 ohms emitter resistors (R7, R34) with 10 ohms and remove the 4.7 ohm resistors (R32, R4).
5. In the last IF amplifier, we change the load resistor(R33) from 51 ohms to 220 ohms.

You need a few 10 ohms resistors and a 220 ohm resistor. You can resuse the R31 at R18.


Attached are the images and the circuit.

73, f 

Re: #Antuino: an update and a bit of bad news for those bought it at FDIM-2019

Ashhar Farhan
 

I'll add two things :
1. I have worked on this with Raj, who went potty trying to figure this out. I am driving down to bangalore, on sunday, we will together review these changes (two pairs of eyes are better than one). 
2. I hope to have the final production Antuinos up on the website by the end of next week, two months late! Expect the price to be $100 inclusive of shipping.
- f 

On Fri, Jul 26, 2019 at 10:46 PM Ashhar Farhan via Groups.Io <farhanbox=gmail.com@groups.io> wrote:
Peeps,
The Antuino has been in use for over a few months now. We had produced 100 of them that were sold at the FDIM. These work quite well for an SWR meter and Antenna Analyzer, but they were sub-optimal for serious RF work. For those who bought it for SWR measurements, you can continue to use it. For those who want to improve it, read on.

It was noticed that the db scale was not accurate. Antuino was designed to be an accurate and precise instrument. The db readings should be within +/- 1 db accuracy. However, they tended to vary by as much as 2 db on the upper range of power measurments. This was finally tracked down to having too much gain. I had prototyped the original with 2N3904 transistors but in production we used BFR93W as I guessed it would have 'better' performance. It turned to be a bad choice. The higher gain resulted in compression of signals above -30 dbm. This restricted the useful range of the Antuino to about 50 db. 

I am attaching the new (Version 2.1, it is a minor edit of the V2 that was sold at the FDIM). In summary, these are the changes:
1. The new software with a cleaner way to calibrate is on https://github.com/afarhan/antuinov2.1. Please upgrade to it even if you don't want to carry out the other hardware modifications.
2. Replace the Q1 and Q3 transistors to 2N3904. Although the PCB pads are SMT, you can solder the leaded type by twisting the legs around.
3. In the first IF amplifier (that immediately follows the mixer), we decrease the emitter resistor (R18) from 100 ohms to 51 ohms (you can also parallel a regular 1/4 watt 100 ohms with the original 100 ohms to get to 51 ohms). We also parallel the (R19) 220 ohms collector load with a 10 uh inductor (you can use 10 turns on FT 37-43), the exact value is not important.
4. In the second and third IF amplifiers, we replace the 100 ohms emitter resistors (R7, R34) with 10 ohms and remove the 4.7 ohm resistors (R32, R4).
5. In the last IF amplifier, we change the load resistor(R33) from 51 ohms to 220 ohms.

You need a few 10 ohms resistors and a 220 ohm resistor. You can resuse the R31 at R18.


Attached are the images and the circuit.

73, f 

Re: #Antuino: an update and a bit of bad news for those bought it at FDIM-2019

Gordon Gibby
 

​That would be fantastic....i'll be buying one immediately.

Gordon Gibby KX4Z



From: BITX20@groups.io <BITX20@groups.io> on behalf of Ashhar Farhan <farhanbox@...>
Sent: Friday, July 26, 2019 2:03 PM
To: BITX20@groups.io
Subject: Re: [BITX20] #Antuino: an update and a bit of bad news for those bought it at FDIM-2019
 
I'll add two things :
1. I have worked on this with Raj, who went potty trying to figure this out. I am driving down to bangalore, on sunday, we will together review these changes (two pairs of eyes are better than one). 
2. I hope to have the final production Antuinos up on the website by the end of next week, two months late! Expect the price to be $100 inclusive of shipping.
- f 

On Fri, Jul 26, 2019 at 10:46 PM Ashhar Farhan via Groups.Io <farhanbox=gmail.com@groups.io> wrote:
Peeps,
The Antuino has been in use for over a few months now. We had produced 100 of them that were sold at the FDIM. These work quite well for an SWR meter and Antenna Analyzer, but they were sub-optimal for serious RF work. For those who bought it for SWR measurements, you can continue to use it. For those who want to improve it, read on.

It was noticed that the db scale was not accurate. Antuino was designed to be an accurate and precise instrument. The db readings should be within +/- 1 db accuracy. However, they tended to vary by as much as 2 db on the upper range of power measurments. This was finally tracked down to having too much gain. I had prototyped the original with 2N3904 transistors but in production we used BFR93W as I guessed it would have 'better' performance. It turned to be a bad choice. The higher gain resulted in compression of signals above -30 dbm. This restricted the useful range of the Antuino to about 50 db. 

I am attaching the new (Version 2.1, it is a minor edit of the V2 that was sold at the FDIM). In summary, these are the changes:
1. The new software with a cleaner way to calibrate is on https://github.com/afarhan/antuinov2.1. Please upgrade to it even if you don't want to carry out the other hardware modifications.
2. Replace the Q1 and Q3 transistors to 2N3904. Although the PCB pads are SMT, you can solder the leaded type by twisting the legs around.
3. In the first IF amplifier (that immediately follows the mixer), we decrease the emitter resistor (R18) from 100 ohms to 51 ohms (you can also parallel a regular 1/4 watt 100 ohms with the original 100 ohms to get to 51 ohms). We also parallel the (R19) 220 ohms collector load with a 10 uh inductor (you can use 10 turns on FT 37-43), the exact value is not important.
4. In the second and third IF amplifiers, we replace the 100 ohms emitter resistors (R7, R34) with 10 ohms and remove the 4.7 ohm resistors (R32, R4).
5. In the last IF amplifier, we change the load resistor(R33) from 51 ohms to 220 ohms.

You need a few 10 ohms resistors and a 220 ohm resistor. You can resuse the R31 at R18.


Attached are the images and the circuit.

73, f 

Re: #Antuino: an update and a bit of bad news for those bought it at FDIM-2019

 

link to the GLCD or compiled hex please? I did the hardware mods but don't have and cant find the GLCD modded lib.........
--
David

 N8DAH
Kit-Projects.com

Shop is open!

Operating uBITZ

Liam Kingsmill <lumetters1@...>
 

I've found no guide to operating the uBITZ,  Is there one?
How do I wire the included mike and push button switch?
If an included unwired (mic ?) plug is inserted in the mic jack, "TX" appears on the screen.  What does that mean?

Re: #Antuino: an update and a bit of bad news for those bought it at FDIM-2019

 

using the stock firmware looking good hope I can get the GLCD modded lib or someone with it is kind enough to post a hex. Here is the new sweep of the BCI filters much better over all readings by a large margin.


--
David

 N8DAH
Kit-Projects.com

Shop is open!

Re: #Antuino: an update and a bit of bad news for those bought it at FDIM-2019

Ashhar Farhan
 

The glcd library is at http://www.hfsignals.com/wp-content/uploads/2019/07/glcd.zip
I will add it to the repo. It is ummodified from what you already have. Run the calibration once, though.

On Sat 27 Jul, 2019, 7:00 AM N8DAH, <Dherron@...> wrote:

using the stock firmware looking good hope I can get the GLCD modded lib or someone with it is kind enough to post a hex. Here is the new sweep of the BCI filters much better over all readings by a large margin.


--
David

 N8DAH
Kit-Projects.com

Shop is open!

Re: #Antuino: an update and a bit of bad news for those bought it at FDIM-2019

Ashhar Farhan
 

I have added the glcd library to the repo.

- f

On Sat, Jul 27, 2019 at 7:34 AM Ashhar Farhan via Groups.Io <farhanbox=gmail.com@groups.io> wrote:
The glcd library is at http://www.hfsignals.com/wp-content/uploads/2019/07/glcd.zip
I will add it to the repo. It is ummodified from what you already have. Run the calibration once, though.

On Sat 27 Jul, 2019, 7:00 AM N8DAH, <Dherron@...> wrote:

using the stock firmware looking good hope I can get the GLCD modded lib or someone with it is kind enough to post a hex. Here is the new sweep of the BCI filters much better over all readings by a large margin.


--
David

 N8DAH
Kit-Projects.com

Shop is open!

Anyone ordering in China? About the shipment's tax

Yaolin Pan
 

Have any ham in China bought uBITX? I recently ordered one, and the logistics sent me DHL. I heard about that this company is notorious and will seize every opportunity to collect taxes. Then I email consulted HF Signal. They said that the electronic kits was written outside the package. I wonder if this will be taxed?

Re: Operating uBITZ

Liam Kingsmill <lumetters1@...>
 

UPDATE:  One which is a correction ... in the third sentence  "Un-wired (mic ?) plug ..."    should read "somehow defecttve (mic ?) plug  "  The plug was not part of the uBITX kid.  It is a mono plug factory assembled to a two wire shielded cable.  Plug it it and "TX" shows on the LCD.

Unless capacitance in the copper shielded cable caused the "TX" to show in the LCD, I'm stumped. 

However, a second test ... different plug from kit ( stereo) with two wires soldered to the tip and shield ... did not cause "TX" to show whether the tip and shield were shorted together or open circuit.

Ver 5.1 PC board.

Re: Operating uBITZ

 

Hi,

A mono plug inserted into a stereo socket will short the ring connection to ground and thus engage the PTT.  See the wireup diagram on the groups.io wiki section.

Re: Operating uBITZ

Darwin EI3IHB
 

Re: Operating uBITZ

Olivier Grand
 

Hello !
Have a look on attached file.
73 Olivier

Le sam. 27 juil. 2019 à 00:45, Liam Kingsmill <lumetters1@...> a écrit :
I've found no guide to operating the uBITZ,  Is there one?
How do I wire the included mike and push button switch?
If an included unwired (mic ?) plug is inserted in the mic jack, "TX" appears on the screen.  What does that mean?