Date   
Re: BITX 40 SMD GROUP

Jerry Gaffke
 

Scratch build traffic will be pretty rare going forward with the availability of the Bitx40, not sure banning it would gain much.  What little scratch build traffic we get is generally well informed and to the point, most of the fluff here is enthusiastic new Bitx40 owners.  The Bitx40 is meant to be hacked, will have various bands and analog/si5351 vfo's just like scratch builds.  Subject line should identify what you got if not a standard issue Bitx40.  Would be nice to archive all that decade of old photos and files at some point, have a system going forward to make stuff easier to find.  Before word gets out and this Bitx40 thing really takes off.

No strongly held opinions here.  I did mention the possibility of a new Bitx40 group in a previous post as one possible way to get around the clutter in files/photos.  But the few extra posts don't strike me as burden, so long as they are clear about what they got.


Re: BITX 40 SMD GROUP

len.walton@...
 

Couldn't agree more .

Re: BITX 40 SMD GROUP

Lawrence Macionski <am_fm_radio@...>
 

My vote is YES... I have a BITX40 SMD semi kit with Raduino... not a through the hole BITX20 with analog VFO...Frankly- Some of these guys get carried away, with a whole multitude of things that

#1 makes reading posts tiring, (see #4)

#2 has little to do with my aspirations and my specific unit.

#3. It off loads running out of space for (and the ability to) uploads-- As we saw this past week..

#4. Let other  BITX40 groups like the one on FACEBOOK kibitz, brag, post QSO's, shout outs, post build pictures and keep this one  technical.

      This would be -mods, improvements, trouble shooting and software updates. Make this kind of a second tier. higher level engineering  

#5. Why cover DC to light? It muddy's the waters and dilutes the experience..

      Let Facebook take the- where can I buy one, Can I pay without paypal? questions.


Re: SDR kits VFO

Marc Jones
 

Thankyou, I shall try 26 MHz when I get chance ....

Much appreciated .

On Wed, 8 Feb 2017 at 14:14, Ashhar Farhan
<farhanbox@...> wrote:
If you set the VFO frequency to 26 MHz, the sideband is automatically inverted. You will not need to move the BFO from LSB to USB for 14 MHz.

- f

On Wed, Feb 8, 2017 at 7:13 PM, Marc Jones via Groups.Io <gw0wvl@...> wrote:
Hi Joel, I've tried all sorts of different frequencies in the IF fir the SDR VFO, If I take  the frequency just below 12 MHz all that happens is that  Transmit /Receive frequency is off by a few KHz .. Etc... So the display on the SDR kits VFO might show 7.100 but I'm actually on 7.098 .. But still on USB . and visa versa ..but all the time it USB..

Marc Gw0wvl


On Tue, 7 Feb 2017 at 14:12, Raj vu2zap
<vu2zap@...> wrote:
Oops it was 11.998500

At 07/02/2017, you wrote:
What worked for me is 1.99985

At 07/02/2017, you wrote:
Mark,

You need to set the IF to 11998000 because you subtract the BFO frequency from the IF.

Joel
KB6QVI

On Feb 7, 2017, at 5:46 AM, Marc Jones via Groups.Io < gw0wvl@...> wrote:

I've recently built a SDR kits VFO (3.5 to 160 MHz) .. It's working fine, But when I connect it to my BITX-40 the LSB is flipped to USB .. I've put the IF as 12.0 MHz and the VFO range is 4.8 -5 MHz .. To cover 7.0 -7.200 ... Any ideas why it flips the Sideband ?

Regards Mark


Re: SDR kits VFO

Ashhar Farhan
 

If you set the VFO frequency to 26 MHz, the sideband is automatically inverted. You will not need to move the BFO from LSB to USB for 14 MHz.

- f

On Wed, Feb 8, 2017 at 7:13 PM, Marc Jones via Groups.Io <gw0wvl@...> wrote:
Hi Joel, I've tried all sorts of different frequencies in the IF fir the SDR VFO, If I take  the frequency just below 12 MHz all that happens is that  Transmit /Receive frequency is off by a few KHz .. Etc... So the display on the SDR kits VFO might show 7.100 but I'm actually on 7.098 .. But still on USB . and visa versa ..but all the time it USB..

Marc Gw0wvl


On Tue, 7 Feb 2017 at 14:12, Raj vu2zap
<vu2zap@...> wrote:
Oops it was 11.998500

At 07/02/2017, you wrote:
What worked for me is 1.99985

At 07/02/2017, you wrote:
Mark,

You need to set the IF to 11998000 because you subtract the BFO frequency from the IF.

Joel
KB6QVI

On Feb 7, 2017, at 5:46 AM, Marc Jones via Groups.Io < gw0wvl@...> wrote:

I've recently built a SDR kits VFO (3.5 to 160 MHz) .. It's working fine, But when I connect it to my BITX-40 the LSB is flipped to USB .. I've put the IF as 12.0 MHz and the VFO range is 4.8 -5 MHz .. To cover 7.0 -7.200 ... Any ideas why it flips the Sideband ?

Regards Mark


Re: SDR kits VFO

Marc Jones
 

Hi Joel, I've tried all sorts of different frequencies in the IF fir the SDR VFO, If I take  the frequency just below 12 MHz all that happens is that  Transmit /Receive frequency is off by a few KHz .. Etc... So the display on the SDR kits VFO might show 7.100 but I'm actually on 7.098 .. But still on USB . and visa versa ..but all the time it USB..

On Tue, 7 Feb 2017 at 14:12, Raj vu2zap
<vu2zap@...> wrote:
Oops it was 11.998500

At 07/02/2017, you wrote:
What worked for me is 1.99985

At 07/02/2017, you wrote:
Mark,

You need to set the IF to 11998000 because you subtract the BFO frequency from the IF.

Joel
KB6QVI

On Feb 7, 2017, at 5:46 AM, Marc Jones via Groups.Io < gw0wvl@...> wrote:

I've recently built a SDR kits VFO (3.5 to 160 MHz) .. It's working fine, But when I connect it to my BITX-40 the LSB is flipped to USB .. I've put the IF as 12.0 MHz and the VFO range is 4.8 -5 MHz .. To cover 7.0 -7.200 ... Any ideas why it flips the Sideband ?

Regards Mark

Tips n Mods

G4NQX <tasmod@...>
 

Just to let you all know that the latest Tips n Mods is in the first folder in the Files section.
--
Rob G4NQX

New file uploaded to BITX20@groups.io

BITX20@groups.io Notification <BITX20+notification@...>
 

Hello,

This email message is a notification to let you know that a file has been uploaded to the Files area of the BITX20@groups.io group.

File: BITX40 with Raduino tips7Feb2017.pdf

Uploaded By: Robert Lane

Description:
Tips n Mods pdf

You can access this file at the URL:
https://groups.io/g/BITX20/files/1%20docs%20of%20Tips%20n%20Mods/BITX40%20with%20Raduino%20tips7Feb2017.pdf

Cheers,
The Groups.io Team

Re: New BITX40 on the air.

 

Ed, I'll have to report you to the society for the prevention of cruelty to waves.
You did not allow one wavelength to complete its journey to the receiver!

Raj

At 08/02/2017, you wrote:
1st contact, 6 feet, work bench to work bench. Sounded good.
Ed

Re: Click on keying ptt

Daniel Corwin
 

Reading this file about the LM386 http://www.ee.ic.ac.uk/pcheung/teaching/DE1_EE/Labs/LM386.pdf it seems plausible. Normally the bypass pin would be used to help filter out noise from the PSU via a cap to ground. Give it a shot and let us know what happens! Connecting it right to ground shouldn't be a problem there's already a 15k ohm resistor built into the chip.

Re: New BITX40 on the air.

Jerry Gaffke
 

Does that cw note have any power behind it that you can see going out the antenna connector into a dummy load, or is this just some residual carrier you can monitor on a nearby receiver?  Inspect T4 closely for broken or shorted leads (and all those other transformers as well).  When transmitting, is there any signal across C107 (voltmeter a good start here, scope if you have it)?


On Tue, Feb 7, 2017 at 08:57 pm, jerry grzelak wrote:

No ssb modulation

Press the ptt  no modulation with no mic she puts out a cw note o well kg6mn

 

 

Re: New BITX40 on the air.

jerrygkg6mn@...
 

No ssb modulation

Press the ptt  no modulation with no mic she puts out a cw note o well kg6mn

 

Sent from Mail for Windows 10

 

From: Jason N3YUG
Sent: Tuesday, February 7, 2017 5:57 PM
To: BITX20@groups.io
Subject: [BITX20] New BITX40 on the air.

 

Got my BITX-40 this evening.  Built it up and got it working well.  I had a inductor with a broken wire, but after soldering it back on the board, all works great.  First contact was IK8ETA, then a Florida station.  Good stuff on 7W!

 

Look forward to getting this thing boxed up and looking better!

 

 

Jason

N3YUG

 

 

 

Re: New BITX40 on the air.

Larry Acklin
 

Only by the Bureau (Dresser☺)

Congrats
Larry KB3CUF




Sent from my Galaxy Tab® E

-------- Original message --------
From: G4NQX <tasmod@...>
Date: 2/7/2017 21:43 (GMT-05:00)
To: BITX20@groups.io
Subject: Re: [BITX20] New BITX40 on the air.

Will the bench qsl ?
--
Rob G4NQX

Re: New BITX40 on the air.

G4NQX <tasmod@...>
 

Will the bench qsl ?
--
Rob G4NQX

Re: New BITX40 on the air.

ekelley
 

After seeing a Shrink for twelve years, he said something that brought
me to tears.
"No hablo ingles"

On the other hand, no tears, My Bitx40 finally works.
1st contact, 6 feet, work bench to work bench. Sounded good.
Ed

New BITX40 on the air.

Jason N3YUG
 

Got my BITX-40 this evening.  Built it up and got it working well.  I had a inductor with a broken wire, but after soldering it back on the board, all works great.  First contact was IK8ETA, then a Florida station.  Good stuff on 7W!


Look forward to getting this thing boxed up and looking better!



Jason

N3YUG



Re: Click on keying ptt

Allard PE1NWL
 

I have a loud "ptt-click" too in my BITX40.
I read some articles about the LM386 where it was mentioned that grounding pin 7 can be used to temporarily mute the audio.
Perhaps this feature could be used to cure the "ptt click", just by switching pin 7 to ground during transmit. Has anyone already tried this?

73, Allard

Re: Possible PA low output problem.

Jerry Gaffke
 

That figure could vary widely depending on how your ohmmeter is built and the charge state of the battery in it.

Jerry, KE7ER


On Tue, Feb 7, 2017 at 02:55 pm, Randy Hall wrote:

I measure about 14K between pin 2 and ground in both directions.

 

Re: BITX 40 SMD GROUP

N7PXY <hickspj467@...>
 

Hey gang,

That would be me that set up a yahoo group for pnw builders.

I don't know how or why I became the focus of email flow for builders in the Radio Club of Tacoma and the pQRP group but it very quickly got way out of hand. People were left off the email list, adding them and getting everyone to use the larger list was impossible, and my time is better spent playing with my BITX40. My only recourse was to centralize the listees and encourage all to seek out the other groups that traded BITX40 info. So I started a yahoo group pnwBITX40Builders. Where it goes is up to the members... I guess.

I just don't have time for it.

73,

PJH, N7PXY

Re: Possible PA low output problem.

Randy Hall
 

Tom

I measure about 14K between pin 2 and ground in both directions.

Randy


On Tue, Feb 7, 2017 at 12:22 PM, tcmedlin1 via Groups.Io <tcmedlin1@...> wrote:

Been a ham for 54 Years and engineer professionally. The low power on the new radiuno has me stumped.    I have set up side by side an original bitx40 and the newer radiuno.  My bitx40 does about 7  watts with 12 v.    I am feeding a 1004 Hz sine wave into both units and making measurements into 50 ohm dummy loads.  All voltages are pretty much in line between the bitx40 and the radiuno. The radiuno only does 1 watt.   After putting a scope on the radiuno I found some interesting things.  when transmitting the scope shows that the signal level is very reduded.  This starts just about at the output of the mic amp Q12  and goes up through the trifilar transformer and then on to the input of Q6.  This level is about 1/3 of what it is in the bitx40.  I think the low power output is being caused by low drive of the audio signal but I can not seem to locate the issue.  I have removed the trifilar transforme to make sure there were no shorts. 

There is one change i see between the bitx40 and the radiuno.     Farhan has take out the two diodes and R106  and replaced that with a single dual diode (surface mount)  I removed the dual diode and measured front to back and they are ok..   Not much to go wrong in this circuit but I still can not see it. Here is one measurement that I can not quite understand.    At pin 2 of the trifilar transformer T4   on the bitx40 (which is working i get resistance measurements of 292k ohm and reversed i get 1.6 Meg ohms. Now on the radiuno i get 14K ohms and reversed i get 81K ohms.  This is a big difference. I believe it is caused by the new smd dual diode.   Any ideas?

Tom W5KUB