Re: Is my BitX output stable?
?Gene, > Do you believe one of these may also be affectng?the freq output changing (which bothers me more than the volume change)?
That business of the transmit frequency moving 50khz is very weird,
can't imagine why it would do that. ?
> Pressed PPT with no mic.? Freq meter jumps between 7.2364 and ~7.2911
> (first number stable second varies 50-60 Khz above first).? Is this normal?? Am I just seeing noise??
I'm not convinced this is real,?
A SingleSideBand transmitter with no input at the mike will not transmit anything at all.
Well, a perfect one would not, you will have some residual carrier, but not at all clear if the freq meter
has sufficient signal, or perhaps it is being overloaded. ?Perhaps it is even seeing some other stuff
like BFO or VFO getting coupled in there to confuse things.
Can you find somebody with a shortwave receiver that has a bfo suitable for receiving an SSB signal?
Here's a cheap one: ?
And cheaper still: ?
Or get one of these, I hear the receiver on it is pretty good: ?
I would recommend doing Allard's 10k resistor mod so you can transmit a CW carrier with key down.
That should be a clear tone in any shortwave receiver with a bfo.
If you don't supply power to the IRF510 at the PA-PWR1 connector, you wont be transmitting anything
and won't need a dummy load but a nearby receiver should still hear a signal from Q14.
?
It's possible the BFO or VFO really are moving around, that's the only way this frequency change could be real.
You can listen to our BFO using that same sw receiver tuned to 12mhz. ?With the Bitx40 tuned to 7.2mhz
the VFO will be found on your radio dial at 12-7.2 = 4.8mhz.
Jerry
On Sat, Nov 18, 2017 at 07:58 pm, Gene Nitschke wrote:
?
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As a temporary measure , one could solder a 1/4 w mfr? mounting it vertically.
?It should suffice.
On Sun, Nov 19, 2017 at 9:36 AM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote: As Raj has noted previously, R141 is working very hard there and tends to overheat.
Check it by putting an ohmmeter across it with power to the board off,
if you see much more than 10 ohms it needs to be replaced.
Since it probably burned open, you could just add something in parallel,
preferably a bigger resistor. The existing 1206 size surface mount resistor is rated for 1/8 watt.
So perhaps a 10 ohm 1/4 watt resistor, or two 20 ohm 1206 resistors in parallel.
On Sat, Nov 18, 2017 at 07:39 pm, Raj vu2zap wrote:
This is usually failure of R141. Check and replace.
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As Raj has noted previously, R141 is working very hard there and tends to overheat.
Check it by putting an ohmmeter across it with power to the board off,
if you see much more than 10 ohms it needs to be replaced.
Since it probably burned open, you could just add something in parallel,
preferably a bigger resistor. The existing 1206 size surface mount resistor is rated for 1/8 watt.
So perhaps a 10 ohm 1/4 watt resistor, or two 20 ohm 1206 resistors in parallel.
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On Sat, Nov 18, 2017 at 07:39 pm, Raj vu2zap wrote:
This is usually failure of R141. Check and replace.
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Re: Strange tuning problem on BitX-40
Would be interesting to hack the script to display the analog reading from the tuning pot pin on the second line.
Might try adjusting the script to move the tuning pot to some other analog pin.
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On Sat, Nov 18, 2017 at 07:39 pm, Raj vu2zap wrote:
Does the purple wire vary from 0 to 5V when your turn the pot ?
If it does then it could be the nano.
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Re: Is my BitX output stable?
Jerry, Raj,
Thanks for?the feedback.? I will try going back to an earlier version and see if that changes things as that is easiest change.? Will then try removal of the 100pf and finally moving antenna to C5/C6 junction (with L3 disconnected).? Do you believe one of
these may also be affectng?the freq output changing (which bothers me more than the volume change)?
The 2nd BitX is still in the box unpacked but maybe it is time to find some space on the bench for another one!
Gene N2IJF
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I'm with Allard (hard to imagine how this is firmware related) and Raj (most likely the BPF at L1,2,3).
Though conceivable that the 100pf cap has something to do with it.
> ?I did not perceive this volume change when running V1.01?
Is it possible it was there with v1.01 but you did not notice
it?
If you have a second Bitx40v3 with original firmware, then check for the same symptom there.
Do all the mods you did to your first unit one by one, checking after each to see if the symptom has come on.
Jerry, KE7ER
On Sat, Nov 18, 2017 at 07:30 pm, Gene Nitschke wrote:
The actual volume out of he speaker (mainly noise) increases significantly (3-4X) while tuning across the range mentioned?.? I only have a 1Mhz USB scope but voltage waveform confirms voltage increase to the speaker.??The increase appears to start after
the 7.200 beep but increases until max range 7.300.? I did not perceive this volume change when running V1.01 but I must admit I have not tried any other versions.??
?
My v3?unit is mostly stock with only mods being the?100pf cap to the output low pass filter, and the double diode to protect Q13.? The main reason for upgrading was I was seeing the?freq jumping at the output. The upgrade did not change that so maybe
I should try a down grade of the?SW maybe to something in?between V1.01 and 1.27.1?? I want to keep this one mainly stock as I want to build another for experimenting but want?to get this one?right first.
?
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Re: Is my BitX output stable?
I'm with Allard (hard to imagine how this is firmware related) and Raj (most likely the BPF at L1,2,3). Though conceivable that the 100pf cap has something to do with it.
> ?I did not perceive this volume change when running V1.01?
Is it possible it was there with v1.01 but you did not notice it?
If you have a second Bitx40v3 with original firmware, then check for the same symptom there.
Do all the mods you did to your first unit one by one, checking after each to see if the symptom has come on.
Jerry, KE7ER
On Sat, Nov 18, 2017 at 07:30 pm, Gene Nitschke wrote:
The actual volume out of he speaker (mainly noise) increases significantly (3-4X) while tuning across the range mentioned?.? I only have a 1Mhz USB scope but voltage waveform confirms voltage increase to the speaker.??The increase appears to start after the 7.200 beep but increases until max range 7.300.? I did not perceive this volume change when running V1.01 but I must admit I have not tried any other versions.??
?
My v3?unit is mostly stock with only mods being the?100pf cap to the output low pass filter, and the double diode to protect Q13.? The main reason for upgrading was I was seeing the?freq jumping at the output. The upgrade did not change that so maybe I should try a down grade of the?SW maybe to something in?between V1.01 and 1.27.1?? I want to keep this one mainly stock as I want to build another for experimenting but want?to get this one?right first.
?
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Re: Strange tuning problem on BitX-40
Time for a meter recal ?
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At 18/11/2017, you wrote: The voltage actually at the 7805 is 4.91v. This is using a Fluke 75
digital multimeter that I have checked against other known sources. I
have changed the 7805 and the voltage is still the same!!!!
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Re: Strange tuning problem on BitX-40
Does the purple wire vary from 0 to 5V when your turn the pot ?
If it does then it could be the nano.
Raj
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At 18/11/2017, you wrote: I have changed the pot - no difference. I have disconnected the purple
green and yellow wires from the pot and measured the voltages very
accurately. They are Purple wire 1.855v, Green Wire 4.91v and yellow
wire 0v.
I am still stumped. Could the problem be in the actual Arduino?
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Phil,
This is usually failure of R141. Check and replace.
Raj, vu2zap
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At 18/11/2017, you wrote: Hi there
First off, I am a complete novice so I'm flying blind here. After a successful build, my Bit X 40 was producing about 7 watts PEP. It's now producing less than a watt (my meter doesn't go any lower). It is transmitting as I can hear my signal through a receiver, but it's registering nothing on the power meter. After wiring up the speaker tonight due to a poor connection, upon reassembling the case and powering up the display flashed on and off and then settled down. It's receiving okay but next to no power.
If anyone can help with a big dummies guide to step by step checking it that would be great. I'm a new amateur and lack sophisticated test gear and in depth knowledge. I've also not had experience with Arduino boards.I've read some posts here and they are very technical and seem to assume a lot of prior knowledge. For instance, one post suggests for low power, checking the output of U3. I can't even find this component on the circuit diagram!
I fear this may become a door stopper if I can't fix it :(
Hope you can help
cheers, Phil
VK8VWA
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Re: Is my BitX output stable?
The actual volume out of he speaker (mainly noise) increases significantly (3-4X) while tuning across the range mentioned?.? I only have a 1Mhz USB scope but voltage waveform confirms voltage increase to the speaker.??The increase appears to start after
the 7.200 beep but increases until max range 7.300.? I did not perceive this volume change when running V1.01 but I must admit I have not tried any other versions.??
My v3?unit is mostly stock with only mods being the?100pf cap to the output low pass filter, and the double diode to protect Q13.? The main reason for upgrading was I was seeing the?freq jumping at the output. The upgrade did not change that so maybe
I should try a down grade of the?SW maybe to something in?between V1.01 and 1.27.1?? I want to keep this one mainly stock as I want to build another for experimenting but want?to get this one?right first.
Gene N2IJF
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On Fri, Nov 17, 2017 at 08:10 pm, Gene Nitschke wrote:
With V1.27.1 the volume significantly increases while tuning between 7.230 and 7.300.? This did not occur with V1.01 loaded.? Is this normal?
It is hard to believe that the volume increase could have anything to do with the software.
The software only controls the VFO frequency, not the volume of the audio amplifier nor anything in the RF receive signal path.
What do you mean exactly by 'volume'?
The volume of the audio amplifier? Or is the sensitivity increased making all received signals (as well as the background noise) sound louder?
73 Allard PE1NWL
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Re: I appear to have damaged the raduino board in my bitx-40. Does anyone know how I can purchase this separately? It seems impossible to email HFsigs and there is no option on their web page.
Further comment, Jim - and anyone else - Spam-bots can't decipher ASCII-Art. I replace the 'd' of my address with "[)". Put that into a Courier font (standard in a text-editor) and you'll see a capital-d. "/-\" for A, "][" for I ... the young'uns get it - they use it extensively.
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Re: I appear to have damaged the raduino board in my bitx-40. Does anyone know how I can purchase this separately? It seems impossible to email HFsigs and there is no option on their web page.
On 11/18/2017 5:16 PM, Michael Hagen
wrote:
?
Much better than
Raduino.
Alternate PCB is
RaduinoX.
?
Bare PCB is $10,
includes shipping and PayPal.
Assembled PCB is
$38,? includes shipping and $2 for PayPal = $40.
New Nano, Plugs into
sockets add $4.
New LCD, just like
original, Yellow 2X16 add $5.
3D Printed Bezel
Kit, includes Hardware add $4.
So let me know what
you want and if you need more Info?
Shipping to Foreign
is probably? about $14, 3x4x2" Box.
Thanks
Mike, WA6ISP
motdog@...
On 11/18/2017 4:58 PM, Jerry Gaffke
via Groups.Io wrote:
Not sure why you
can't buy a Raduino from hfsigs.com if that's what you want.
Near the bottom of the buy page:
??
you should see this text:
########################
Buy the Raduino for $25 with free shipping
($10 extra for DHL Shipping)
The Raduino is a general purpose,
programmable board that can be used as a VFO, controller, in
your radio projects.
It comes bundled with the BITX40 kit. This is an option for
those who wish to use the Raduinio in other projects
Box Contents
- 1 x Raduino board
- 1 x 5-pin connector pair (for attaching the Raduino to the
BITX and power supply)
- 1 x 8-pin connector pair (for attaching the Raduino to the
front )
- 8 x Half-inch brass stand-offs
- 8 x M3 mounting bolts screws
- 4 x M3 mounting nuts
- 1 x 10k linear pot (Tuning)
--
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID "MotDog@..."
Mike@...
--
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID "MotDog@..."
Mike@...
|
Re: I appear to have damaged the raduino board in my bitx-40. Does anyone know how I can purchase this separately? It seems impossible to email HFsigs and there is no option on their web page.
?
Much better than
Raduino.
Alternate PCB is
RaduinoX.
?
Bare PCB is $10,
includes shipping and PayPal.
Assembled PCB is $38,?
includes shipping and $2 for PayPal = $40.
New Nano, Plugs into
sockets add $4.
New LCD, just like
original, Yellow 2X16 add $5.
3D Printed Bezel Kit,
includes Hardware add $4.
So let me know what
you want and if you need more Info?
Shipping to Foreign is
probably? about $14, 3x4x2" Box.
Thanks
Mike, WA6ISP
motdog@...
On 11/18/2017 4:58 PM, Jerry Gaffke via
Groups.Io wrote:
Not sure why you
can't buy a Raduino from hfsigs.com if that's what you want.
Near the bottom of the buy page:
??
you should see this text:
########################
Buy the Raduino for $25 with free shipping
($10 extra for DHL Shipping)
The Raduino is a general purpose,
programmable board that can be used as a VFO, controller, in
your radio projects.
It comes bundled with the BITX40 kit. This is an option for
those who wish to use the Raduinio in other projects
Box Contents
- 1 x Raduino board
- 1 x 5-pin connector pair (for attaching the Raduino to the
BITX and power supply)
- 1 x 8-pin connector pair (for attaching the Raduino to the
front )
- 8 x Half-inch brass stand-offs
- 8 x M3 mounting bolts screws
- 4 x M3 mounting nuts
- 1 x 10k linear pot (Tuning)
--
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID "MotDog@..."
Mike@...
|
Re: I appear to have damaged the raduino board in my bitx-40. Does anyone know how I can purchase this separately? It seems impossible to email HFsigs and there is no option on their web page.
If it's Mike's PCBs you're looking for then yes, of course the link he gives won't work. It's not a link to a website, it's a deliberately-mangled (to foil spam-bots' harvesting) email address, so replace "at " with "." and email him. I just did, flawlessly and with prompt reply - good one Mike!
73 de ZL2DEX
|
Re: I appear to have damaged the raduino board in my bitx-40. Does anyone know how I can purchase this separately? It seems impossible to email HFsigs and there is no option on their web page.
Not sure why you can't buy a Raduino from hfsigs.com if that's what you want. Near the bottom of the buy page: ?? you should see this text: ######################## Buy the Raduino for $25 with free shipping ($10 extra for DHL Shipping)
The Raduino is a general purpose, programmable board that can be used as a VFO, controller, in your radio projects.
It comes bundled with the BITX40 kit. This is an option for those who wish to use the Raduinio in other projects
Box Contents
- 1 x Raduino board
- 1 x 5-pin connector pair (for attaching the Raduino to the BITX and power supply)
- 1 x 8-pin connector pair (for attaching the Raduino to the front )
- 8 x Half-inch brass stand-offs
- 8 x M3 mounting bolts screws
- 4 x M3 mounting nuts
- 1 x 10k linear pot (Tuning)
|
Re: I appear to have damaged the raduino board in my bitx-40. Does anyone know how I can purchase this separately? It seems impossible to email HFsigs and there is no option on their web page.
Tried the link you posted but didn't work. I would be interested in your PCBs.
Thanks,
Jim
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From: [email protected] <[email protected]> on behalf of Michael Hagen <motdog@...>
Sent: Friday, November 17, 2017 6:07:14 PM
To: [email protected]
Subject: Re: [BITX20] I appear to have damaged the raduino board in my bitx-40. Does anyone know how I can purchase this separately? It seems impossible to email HFsigs and there is no option on their web page.
?
Yes!? I have an improved version with lots of extras.
So called RaduinoX.
Bare PCB or complete and tested.
Ask the dozen or so folks who bought them.
?
For those wanting a Raduino board.
There is a better option than the orginal Raduino board with it Soldered
- in Nano.
RaduinoX? PCB designed to add some features.
I have Lots of Bare PCBs and some assembled and tested.? Lots of Bare PCBS!
Several sold to guys in this group.
I used this board, LCD, and Rotary Encoder to make a nice dedicated RF
signal generator.
1) I wanted to be able to plug Nano in and out, not soldered. I wanted
the USB connect next to the side of the cabinet so I can program without
taking the lid off.? I will make a small hole.
2) Added, diode protection, more filtering and conditioning on the power
input.? Regulator is bolted down.
3) Added a dedicated connector for Rotary Encoder with pullups and
bounce capacitors.
4) Added an I2C connector.
5) I wanted proper Level Shifting to the Si 3V part.? Added FETs and
pullups for that.
6) Added D0 and D1 pins on PCB.
7) Kept power and VFO connector on 5P header so no changes to my present
wiring was necessary.
8) Put contrast Pot where you can get to it.
9) Complete documentation.
10) Fits original LCD perfectly.
Take a look if you are interested.
motdog@verizon dot net
Mike, WA6ISP
On 11/17/2017 1:50 PM, David Holland wrote:
I appear to have damaged the raduino board in my bitx-40.? Does anyone know how I can purchase this separately?? It seems impossible to email HFsigs and there is no option on their web page.
Dave G4LDT
--
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID "MotDog@..."
Mike@...
|
Re: Strange tuning problem on BitX-40
This is all very strange.
I suspect there may be issues with the wiring (especially with the ground connections).
Or perhaps with the power supply (stability, noise).
Which mods did you install?
For trouble-shooting you could uninstall them and first make sure that the radio basically works without any mod (the software should still basically work without any mod).
Then reinstall them one by one and see when the problem returns.
73 Allard PE1NWL
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Re: Strange tuning problem on BitX-40
Answers to questions and further info:-
OK, so you have 4.91V from the 7805 (let's assume this is still within specs), and this voltage also arrives (without drop) at the one end of the potentiometer.
At the other end you have zero volts.
What reference ground point did you use for these measurements? ? - The actual centre pin of the 780 regulator chip
What voltage do you measure on the slider when it's at either end of the pot? - 0v and 4.91v
Does the slider voltage vary over the full (0V - 4.91V) range when you turn the pot? - Yes
Also noted is that when the pot is at the 5v end the display shows both "Dial is locked" and "TX".
The plot thickens!!!
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I might check your FET. ?You get a little bit of output power even if you blow the IRF510, but not much at all.
You say it was putting out the usual 7w at first, so I wonder if at some point you had an antenna mismatch or open circuit and keyed your mic long enough to damage the IRF510?
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I had the issue of NO power at all.
?I had changed R141 (1o Ohms) on the advise of Raj (vu2zap) . It went open circuit. you may Try thyat.
?The for reduction issue there is a trip pot in Tx sction after? pre driver stage.If it had been readjusted the output power changes.
?Hope thes suggestions help.
regards
?sarma
?vu3zmv
?
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Raj vu2zap
James Lawrie
Allard PE1NWL