Date   
Bitx40v3 SMD ver question

Art Olson
 

Ashhar

purchased a bitx40v3 (smd version). Ordered the DDS vfo fro qrp labs and waiting for it to arrive. I have a FLL Freq Counter Sunil. I think I can use this until the QRP-labs version arrive but has anyone connected a FLL to the current version from you?

art


Re: Broken URL on hfsigs.com

Arv Evans
 

The correct page for HFSigs BITX40v3 is at:

http://www.hfsigs.com/

The URL for the original BITX20 design by Farhan is:

http://www.phonestack.com/farhan/bitx.html

_._

On Wed, Nov 30, 2016 at 7:34 AM, Daniel Morgan kk4mrn@... [BITX20] <BITX20@...> wrote:
 

The Circuit Description page has a broken link.

Instead of:

It should be without the 20:



Re: Bitx40 BPF

Ken
 

Thank you Ashhar.

73 Ken

On Wed, Nov 30, 2016 at 2:42 PM, Ashhar Farhan farhanbox@... [BITX20] <BITX20@...> wrote:
 

It is centered on 7.2 MHz. It is 500 Khz wide

- f

On Wed, Nov 30, 2016 at 7:14 PM, Ken Chase chase8043@... [BITX20] <BITX20@...> wrote:
 

Hi Ashhar

What is the centre frequency and bandwidth of the BPF?

73

Ken VA3ABN



Re: Bitx40 BPF

Ashhar Farhan
 

It is centered on 7.2 MHz. It is 500 Khz wide

- f

On Wed, Nov 30, 2016 at 7:14 PM, Ken Chase chase8043@... [BITX20] <BITX20@...> wrote:
 

Hi Ashhar

What is the centre frequency and bandwidth of the BPF?

73

Ken VA3ABN


Re: Success with BITX

Mike Haynes <mike.haynes08@...>
 

Hi Baruch,
I did the same thing for my microphone, and I'm glad you received a good report on your transmit audio. I was using my SW receiver (with SSB capability) to monitor my transmit audio. Just like you said, it sounded horrible. I haven't made any contacts yet, but your experience gives me hope that I will have the same result as you did.

73
--
Mike Haynes
KE0KRY

Re: LOW tx output1.4 volt

Soundararajan Ra.
 

Dear farhan
After replacing Mic i am able to get  1.5 at 100 preset.
But still power out put is below 4 watt.
Driver transistor DC voltage
ground to emitter 440 mv
Ground to base 1.2 volt
Emitter to base 646 mv
pk to pk 7mhz voltage is
Driver base 1.5 volt
Driver collector 1.4 volt
PA gate 1 volt
Checked for short in toroids .
Shall i replace driver transistor.
I have 2N2218A. Shall i use instead of 2N2219A?.
Any it good experience get more exposure in Bitx.
I am enjoying the experience.
Full joy is ,when come on AIr with 8 watt power.
73s
Soundar
Vu2rjw


On Nov 23, 2016 9:30 PM, "Soundararajan Ra." <vu2rjw@...> wrote:

Dear mr farhan
Realy unble to solve my problem
removed predriver transformer and rewound .
Ground to collector 1.1 v
collector to centret tap .5 volt (both supposed to be added and to get 1.5 v)
But CT to ground is .5 volt (c134).
At 100R preset getting .5 v so insufficient drive voltage .
Getting 2 watt out put at antenna.
I am blinking ,what next 7 do.

One more option for me  is to order one more kit.
Soundar
Vu2rjw.


On Nov 23, 2016 4:41 PM, "ik8yfw@... [BITX20]" <BITX20@...> wrote:
 

I performed some transmissions test Yesterday night, I can confirm the values declared: 100 - 90 mA in RX mode, almost 385 mA pressing PTT and over 1.1 A when modulate. Clear audio. I measure over 7 W output on my wattmeter. Fine job. I planning to add a fan to IRF510 for temperature controll. Thanks. Giuseppe, ik8yfw


Broken URL on hfsigs.com

Daniel Morgan
 

The Circuit Description page has a broken link.

Instead of:

It should be without the 20:


Bitx40 BPF

Ken
 

Hi Ashhar

What is the centre frequency and bandwidth of the BPF?

73

Ken VA3ABN

Bitx40 BPF

Ken
 

Hi Ashhar

What is the centre frequency and bandwidth of the BPF?

73

Ken VA3ABN

Success with BITX

Baruch Atta <baruchatta@...>
 

I am happy to report that I have successfully completed my BITX 40 v3 project.  The board is securely installed in a nice enclosure.  I used a commercial enclosure, $20, steel and aluminum.  I "splurged" and bought a new set of drill bits from Home Depot for $10 to drill the holes (instead of using my rag-tag bunch of second hand tools.) I used the Mic from a surplus old RS CB.  The mic handset includes a push to talk switch.  The jack from the CB is installed in the BITX.  I removed the original mic and installed the BITX supplied microphone in the handset.  

During testing, I was dismayed that the transmit audio was horrible, when listening on my big rig.  But when I arranged a QSO with a nearby ham friend, he gave me a good report.  Success!

There are two issues remaining.  Number one is the loud snap in the earphones when I key the microphone.  Is there anyway to solve that?  Number two is the frequency drift.  The frequency drift seems to settle down after a half hour.  I would like to leave most of the original circuit as is, if I can.  I am thinking of replacing the frequency determining capacitors with mica or polystyrene.  Would that help with the drift?  Has anyone tried this?

Thanks to Ashar for his hard work, made my work easier!  

73, Joe W3TTT

Re: Bitx40 #861 arrived

rjinspace
 

Thank you. It was me. From the photo it seems like 10 turns yes. But the output transformer close to the IRF510 and the LP filter, is it also 10 turns (usually it is 3, I think).

Thanks.
Roy

Re: Toroids Loose on Arrival

ohwenzelph
 

yep, that's pretty much what mine looked like, a bit loose and a bit scramble wound
jerry aa1of/6

Re: Bitx 40 board.

Mark W
 

Thank you!

 

From: BITX20@... [mailto:BITX20@...]
Sent: Tuesday, November 29, 2016 1:26 AM
To: BITX20@...
Subject: RE: [BITX20] Bitx 40 board.

 

 

Mark, This is the official bitx40 hack blog:

http://bitxhacks.blogspot.it

73 Giuseppe, ik8yfw

Re: Toroids Loose on Arrival

Ryan Flowers
 

Hi Joel,

Thanks a lot for that. I've seen that others have had issues, wasn't sure though. I'll try the nail polish trick since I don't have anything else handy. Looks like I have an antenna to erect and some soldering to do!

Thanks,

Ryan Flowers
KC7RYS

My Build progress

DuWayne Schmidlkofer
 

I just updated my blog with the progress I have made on building my BITX 40 board.
Except for a little drift that I am still working on, the receiver portion is working quite well.
Next to check the transmitter portion.

Building the BITX 40p, receiver portion

 

DuWayne KV4QB


Re: Bitx 40

Bill Robbins <wrobbins@...>
 

I just wanted to thank everyone for the help.  My problem turned out to be the 9 volt regulator.  I probably dragged a screwdriver across it while dinking around.


Bill





From: Bill Robbins
Sent: Monday, November 28, 2016 6:27 PM
To: BITX20@... for the help.  My problem turned out to b e a
Subject: Re: [BITX20] Bitx 40 Problem
 

I have another, just arrived, Bitx 40.  Hooked it up and works as it should, at least for receive. 


#67, the first, cannot hear a signal generator putting out 0 dBm  signal.  Running it on a 12 volt battery eliminated a lot of hash.


So I at least know the signal is not making it very far.







From: BITX20@... on behalf of Jeff Glass kg6sgx@... [BITX20]
Sent: Monday, November 28, 2016 5:51 PM
To: BITX20@...
Subject: Re: [BITX20] Bitx 40 Problem
 
 

Do you have a nice strong power source? Like all high-gain LM386 circuits, the audio amp is prone to becoming an oscillator when starved of sufficient power.

Best,
Jeff
KK9JEF

Sent from my iPhone

On Nov 28, 2016, at 4:20 PM, Ken Chase chase8043@... [BITX20] <BITX20@...> wrote:

 

You may also be able to drape it over the antenna connector. Try that first without the antenna connected.

73 Ken

On Mon, Nov 28, 2016 at 5:19 PM, Bill Robbins wrobbins@... [BITX20] <BITX20@...> wrote:
 

Yes I have one. 

Sent from my iPhone

On Nov 28, 2016, at 5:05 PM, Ken Chase chase8043@... [BITX20] <BITX20@...> wrote:

 

Let's rule out the antenna. Do you have a signal source to fed to the antenna input? It has to be very low strenghth around 50 uvolts (S9). If you feed too strong a signal, you may overload the front end.

73 Ken

On Mon, Nov 28, 2016 at 5:02 PM, Bill Robbins wrobbins@... [BITX20] <BITX20@...> wrote:
 

Ken:

Thanks. That's the first thing I did having followed this group. I did spread a few out a little but no help. 

Bill 

Sent from my iPhone

On Nov 28, 2016, at 5:00 PM, Ken Chase chase8043@... [BITX20] <BITX20@...> wrote:

 

Hi Bill

Start by checking that the toroid leads are not shorting together. You can use a toothpick to gentle spread them apart.

73

Ken VA3ABN

On Mon, Nov 28, 2016 at 4:25 PM, billrobbins946@... [BITX20] <BITX20@...> wrote:
 

I decided that you guys are having so much fun that I took out #67 to give it a whirl. 


When powering up I get a very loud buzzing in the ear phones.  So, I power down, remove all external pigtails and then add them one at a time.  It seems to happened when adding the antenna to the circuit board.


Forgive me for asking here but I have little experience with the very small components.


Where to start looking??


Bill




Re: Toroids Loose on Arrival

 

As long as none of the wires are broken on the toroids, all you need to do is straighten them. They pretty much all came with toroids crunched, mine did. For glue, I use hot glue, but you can use silicon or contact cement or anything really. I used to use clear finger nail polish. Don't glue L4 down until you get it on frequency by compressing the turns or loosening them until you get the band coverage you want. You should be on the air soon.

Joel Caulkins
KB6QVI

On Nov 29, 2016, at 4:18 PM, geocrasher@... [BITX20] <BITX20@...> wrote:

 

Howdy all,


I've just received #697 in the mail today, and I sure am excited to get on the air! I did notice a couple of toroids were loose on it, and before I power it up and start playing with it, I want to be sure that they just came unglued and need to be glued back down. Here are pictures of what I see:


L2: http://puu.sh/syTg7/309a86ba3e.jpg


L4:  http://puu.sh/syTiP/c184375c22.jpg (at least, I think this is L4 according to the schematic- it's not visible on the board)


Both of these were oriented incorrectly as seen here:


http://puu.sh/syRFW/b9c675e674.jpg


I straightened them out, but am not sure what to glue them down with. Any assistance would be most appreciated. Thanks!


Toroids Loose on Arrival

Ryan Flowers
 

Howdy all,


I've just received #697 in the mail today, and I sure am excited to get on the air! I did notice a couple of toroids were loose on it, and before I power it up and start playing with it, I want to be sure that they just came unglued and need to be glued back down. Here are pictures of what I see:


L2: http://puu.sh/syTg7/309a86ba3e.jpg


L4:  http://puu.sh/syTiP/c184375c22.jpg (at least, I think this is L4 according to the schematic- it's not visible on the board)


Both of these were oriented incorrectly as seen here:


http://puu.sh/syRFW/b9c675e674.jpg


I straightened them out, but am not sure what to glue them down with. Any assistance would be most appreciated. Thanks!


Re: BITX40 Arrived!

Ryan Flowers
 

BITX40 v3 #697  arrived in Washington State today. Very excited to get on the air with this radio! A couple of toroids are loose however so I'll be posting about that separately. 

Re: Bitx40 audio

Ken
 

I hooked up the speaker and it sounds a million times better with the new cap. Thanks Joel.

73 Ken

On Tue, Nov 29, 2016 at 1:48 PM, caulktel@... [BITX20] <BITX20@...> wrote:
 

Ken,

I changed mine this morning and the receive audio is just about perfect now on a mobile speaker mounted up on my shelve.

Joel
KB6QVI