Date   
Re: Oops..I did it this time....

David Woodward
 

Oh...ok I see it.....nope still a blank screen, but the backlight is on...but the radio is not. Hi...guess somehow I fried the radiuno.
  I was varying the frequency of the bfo  crystal x5, and all the sudden the readout moved to 7.1000 mhz , and it wouldn't tune. So I cut it off, and cut it back on. Now the radio just hisses.

On Jul 8, 2017 10:37 AM, "David Woodward" <kf4wbj2@...> wrote:

Where is the pushbutton?

On Jul 8, 2017 8:04 AM, <greggaston@...> wrote:
I did something similar.  If you hold the pushbutton in while powering up, it will reset the Radinuo to original "factory" settings. 

Greg
KD4VV

Re: Oops..I did it this time....

 

Push button as in the Function switch.

Re: No RF Power Output From Bitx40

David Woodward
 

I use my z-100 antenna tuner all the time to match up a dipole made with twin lead speaker wire...no problem so far (fingers crossed)...

On Jul 8, 2017 10:37 AM, "Richard Andrew Knack via Groups.Io" <ihc73scout2=yahoo.com@groups.io> wrote:
How quickly will IRF-510's blow? And how much power will it take? In other words, if you have a transceiver or an amp that has them for finals, do you have time to use an automatic antenna tuner to get an impedance match? Or will the finals blow while the tuner is running through relays and inductances trying to find a match?

Rich
KC8MWG



On Saturday, July 8, 2017, 10:31:21 AM EDT, Arv Evans <arvid.evans@...> wrote:


K3HJP

Like Raj said...the IRF510 is probably blown, usually due to transmitting into something other
than a 50 ohm load.  If the output impedance is too high the final will go into oscillation and
self-destruct.

Arv  K7HKL
_._

On Sat, Jul 8, 2017 at 7:32 AM, <Kc3hjp@...> wrote:
Hi guys, I finally got around to finishing my Bitx40 project. Everything works but it will not transmit. This has me scratching my head. Here are some details. 

- when I press the PTT on the mic I can hear the relay pull in and receive audio goes away as it should. 
- I've verified that I have 12vdc on the PA connection and it's wired in the right direction. 
- mic element ohms out properly and it's wired in the right direction according to instructions
- 152mA on receive
- 260mA on transmit with no audio
- current may change by .001mA when yelling into the mic
- set PA bios pot makes no difference in current reading with mic keyed (audio/no audio)
- mic element 0.877k ohms in one direction and 1.101k ohms in other direction
- same mic ohm values on the mic connector and board connector
- 12vdc between the Gate and Drain of the PA. No voltage between the Gate and Source when mic is keyed

Any ideas?


Re: Oops..I did it this time....

David Woodward
 

Where is the pushbutton?

On Jul 8, 2017 8:04 AM, <greggaston@...> wrote:
I did something similar.  If you hold the pushbutton in while powering up, it will reset the Radinuo to original "factory" settings. 

Greg
KD4VV

Re: No RF Power Output From Bitx40

Richard Andrew Knack
 

How quickly will IRF-510's blow? And how much power will it take? In other words, if you have a transceiver or an amp that has them for finals, do you have time to use an automatic antenna tuner to get an impedance match? Or will the finals blow while the tuner is running through relays and inductances trying to find a match?

Rich
KC8MWG



On Saturday, July 8, 2017, 10:31:21 AM EDT, Arv Evans <arvid.evans@...> wrote:


K3HJP

Like Raj said...the IRF510 is probably blown, usually due to transmitting into something other
than a 50 ohm load.  If the output impedance is too high the final will go into oscillation and
self-destruct.

Arv  K7HKL
_._

On Sat, Jul 8, 2017 at 7:32 AM, <Kc3hjp@...> wrote:
Hi guys, I finally got around to finishing my Bitx40 project. Everything works but it will not transmit. This has me scratching my head. Here are some details. 

- when I press the PTT on the mic I can hear the relay pull in and receive audio goes away as it should. 
- I've verified that I have 12vdc on the PA connection and it's wired in the right direction. 
- mic element ohms out properly and it's wired in the right direction according to instructions
- 152mA on receive
- 260mA on transmit with no audio
- current may change by .001mA when yelling into the mic
- set PA bios pot makes no difference in current reading with mic keyed (audio/no audio)
- mic element 0.877k ohms in one direction and 1.101k ohms in other direction
- same mic ohm values on the mic connector and board connector
- 12vdc between the Gate and Drain of the PA. No voltage between the Gate and Source when mic is keyed

Any ideas?


Re: No RF Power Output From Bitx40

Curt M.
 

I do not see 5v on any terminal on U3

Re: No RF Power Output From Bitx40

Arv Evans
 

K3HJP

Like Raj said...the IRF510 is probably blown, usually due to transmitting into something other
than a 50 ohm load.  If the output impedance is too high the final will go into oscillation and
self-destruct.

Arv  K7HKL
_._

On Sat, Jul 8, 2017 at 7:32 AM, <Kc3hjp@...> wrote:
Hi guys, I finally got around to finishing my Bitx40 project. Everything works but it will not transmit. This has me scratching my head. Here are some details. 

- when I press the PTT on the mic I can hear the relay pull in and receive audio goes away as it should. 
- I've verified that I have 12vdc on the PA connection and it's wired in the right direction. 
- mic element ohms out properly and it's wired in the right direction according to instructions
- 152mA on receive
- 260mA on transmit with no audio
- current may change by .001mA when yelling into the mic
- set PA bios pot makes no difference in current reading with mic keyed (audio/no audio)
- mic element 0.877k ohms in one direction and 1.101k ohms in other direction
- same mic ohm values on the mic connector and board connector
- 12vdc between the Gate and Drain of the PA. No voltage between the Gate and Source when mic is keyed

Any ideas?


Re: No RF Power Output From Bitx40

 

Possibly. If your final is fine then the bias pot would work.

Check if U3 has 5V out.

At 08/07/2017, you wrote:
So this radio that has never transmitted before and has had a dummy load on it or an antenna every time the mic button has been pressed has a blown final?

Re: No RF Power Output From Bitx40

Curt M.
 

So this radio that has never transmitted before and has had a dummy load on it or an antenna every time the mic button has been pressed has a blown final?

Re: No RF Power Output From Bitx40

 

At 08/07/2017, you wrote:

- set PA bios pot makes no difference in current reading with mic keyed (audio/no audio)
Means final is blown.

- mic element 0.877k ohms in one direction and 1.101k ohms in other direction
I have not checked but I would expect a condensor mic to be open circuit when not connected to board.
Unplug and check.

- same mic ohm values on the mic connector and board connector
- 12vdc between the Gate and Drain of the PA. No voltage between the Gate and Source when mic is keyed

Any ideas?

Re: noise

John Sharpe
 

Thanks Raj,

I’ll try that tomorrow.

At the moment the antenna ground is connected to the case - and the power negative is also connected to the case.
I’ll try isolating the antenna ground,

John

On 8 Jul 2017, at 11:25 pm, Raj vu2zap <@Raj> wrote:

Thats good John,

Now unplug the antenna and just touch the antenna ground to rig rear connector ground.
Nothing should be heard on RX.
If you hear AM signals or noise - probably the socket to board may be an issue or a ground loop.

I have had a similar problem when my jumper cable from rig to SWR meter was frayed and ground
was open.

The antenna ground should be isolated from ground of other rear inputs/outputs. They are all connected
internally on the board.

Raj

At 08/07/2017, you wrote:
Hi Raj,

yes, I understood. From the board to the antenna connector is correct.
I’ve checked for continuity and for any shorts in the connection, but all seems ok.

I'll keep trying - and double checking the connections!

John





On 8 Jul 2017, at 11:11 pm, Raj vu2zap <@Raj> wrote:

Hi John,

Sorry I meant from the board to the antenna connector.

Check with a multimeter on beep continuity if the connections are proper to the connector.

At 08/07/2017, you wrote:
Hi Raj,

I’ve double checked and just now checked again. Centre pin to antenna and shield to ground - all correct.

John





No RF Power Output From Bitx40

Curt M.
 

Hi guys, I finally got around to finishing my Bitx40 project. Everything works but it will not transmit. This has me scratching my head. Here are some details. 

- when I press the PTT on the mic I can hear the relay pull in and receive audio goes away as it should. 
- I've verified that I have 12vdc on the PA connection and it's wired in the right direction. 
- mic element ohms out properly and it's wired in the right direction according to instructions
- 152mA on receive
- 260mA on transmit with no audio
- current may change by .001mA when yelling into the mic
- set PA bios pot makes no difference in current reading with mic keyed (audio/no audio)
- mic element 0.877k ohms in one direction and 1.101k ohms in other direction
- same mic ohm values on the mic connector and board connector
- 12vdc between the Gate and Drain of the PA. No voltage between the Gate and Source when mic is keyed

Any ideas?

Re: noise

 

Thats good John,

Now unplug the antenna and just touch the antenna ground to rig rear connector ground.
Nothing should be heard on RX.
If you hear AM signals or noise - probably the socket to board may be an issue or a ground loop.

I have had a similar problem when my jumper cable from rig to SWR meter was frayed and ground
was open.

The antenna ground should be isolated from ground of other rear inputs/outputs. They are all connected
internally on the board.

Raj

At 08/07/2017, you wrote:
Hi Raj,

yes, I understood. From the board to the antenna connector is correct.
I’ve checked for continuity and for any shorts in the connection, but all seems ok.

I'll keep trying - and double checking the connections!

John





On 8 Jul 2017, at 11:11 pm, Raj vu2zap <@Raj> wrote:

Hi John,

Sorry I meant from the board to the antenna connector.

Check with a multimeter on beep continuity if the connections are proper to the connector.

At 08/07/2017, you wrote:
Hi Raj,

I’ve double checked and just now checked again. Centre pin to antenna and shield to ground - all correct.

John



Re: noise

John Sharpe
 

Hi Raj,

yes, I understood. From the board to the antenna connector is correct.
I’ve checked for continuity and for any shorts in the connection, but all seems ok.

I'll keep trying - and double checking the connections!

John

On 8 Jul 2017, at 11:11 pm, Raj vu2zap <@Raj> wrote:

Hi John,

Sorry I meant from the board to the antenna connector.

Check with a multimeter on beep continuity if the connections are proper to the connector.

At 08/07/2017, you wrote:
Hi Raj,

I’ve double checked and just now checked again. Centre pin to antenna and shield to ground - all correct.

John


Re: noise

 

Hi John,

Sorry I meant from the board to the antenna connector.

Check with a multimeter on beep continuity if the connections are proper to the connector.

At 08/07/2017, you wrote:
Hi Raj,

I’ve double checked and just now checked again. Centre pin to antenna and shield to ground - all correct.

John

Re: Oops..I did it this time....

greggaston@...
 

I did something similar.  If you hold the pushbutton in while powering up, it will reset the Radinuo to original "factory" settings. 

Greg
KD4VV

Re: noise

John Sharpe
 

Hi Raj,

I’ve  double checked and just now checked again. Centre pin to antenna and shield to ground - all correct.

John




On 8 Jul 2017, at 9:45 pm, Raj vu2zap <rajendrakumargg@...> wrote:

Looks like you have interchanged the ground and antenna wires!

Black is ground everywhere in BITX40. Brown is the center pin of BNC or SO239.

Let us know!

Good luck
Raj

At 07/07/2017, you wrote:
Hi all,

I moved my Bitx40 board to a smaller enclosure and somewhere along the line I ended up with massive breakthrough from AM stations.

This happened even with the VFO unplugged from the board.

The breakthrough stopped (surprisingly) when I grounded the centre contact of the antenna input. 7mhz  SSB signals came through fine!

I experimented with a couple of capacitors across the antenna input instead of the grounding, and finally used a 100pf capacitor.
Now the receive is great, no AM breakthrough at all and a reduction in noise. Signals still getting through fine.

Transmit seems ok (on a nearby receiver), but I haven’t tested power output.

I’m not sure how that all worked. I have Peter parker’s improved audio transmit mod. Also removed the 1uf capacitor between pins 1 and 8 of the LM386
and replaced with resistor/capacitor.

Any thoughts?

John

VK2VOL

Re: CW mode delay

Júnior PY2ADA
 

Hello, I realized this problem of delaying cw during a qso. When I transmit for example the letter "P" the bitx40 sends a letter "G". I noticed that the delay appears from 10 PPM up. I really have to send a DIT before any initial transmission. But I am very satisfied with Bitx40 and waiting for the new update.
 
73 from Junior
PY2ADA

Re: noise

 

Looks like you have interchanged the ground and antenna wires!

Black is ground everywhere in BITX40. Brown is the center pin of BNC or SO239.

Let us know!

Good luck
Raj


At 07/07/2017, you wrote:
Hi all,

I moved my Bitx40 board to a smaller enclosure and somewhere along the line I ended up with massive breakthrough from AM stations.

This happened even with the VFO unplugged from the board.

The breakthrough stopped (surprisingly) when I grounded the centre contact of the antenna input. 7mhz  SSB signals came through fine!

I experimented with a couple of capacitors across the antenna input instead of the grounding, and finally used a 100pf capacitor.
Now the receive is great, no AM breakthrough at all and a reduction in noise. Signals still getting through fine.

Transmit seems ok (on a nearby receiver), but I haven’t tested power output.

I’m not sure how that all worked. I have Peter parker’s improved audio transmit mod. Also removed the 1uf capacitor between pins 1 and 8 of the LM386
and replaced with resistor/capacitor.

Any thoughts?

John

VK2VOL

Re: Bitx40 All done

 

Drill very slowly i.e. don't be in a hurry. Acrylic melts and the bit will grab the sheet and spin it and you could get hurt.

I have built many projects with it and even built paddles. I used water to cool the bit and end mills.

I used to save the shavings and dissolve then is a small glass bottle with chloroform and use that as glue.
I learnt this from a local sign board maker in the old days.

Raj

At 08/07/2017, you wrote:
Do you have to be careful when drilling the acrylic to avoid cracking?

Phil, W1PJE