Oh, right. ?You're on 20m, not 40m. ?Return the VFO to wherever the heck it was. ?(Around 2mhz, I assume.) Jerry
On Wed, Feb 8, 2017 at 10:32 am, Jerry Gaffke wrote: you could return the VFO to 5mhz as it was, ?
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Do you have a scope? The signal at T2 should be around 1.6 volts peak to peak. I found that at the higher frequencies, C91 and C92 were attenuating the signal from the SI5351.
This occurred when setting up for 20m with 26 MHZ - 11.99860 MHZ.
73
Ken VA3ABN
On Wed, Feb 8, 2017 at 1:29 PM, Marc Jones via Groups.Io <gw0wvl@...> wrote: I've tried using a 19.0 MHz IF from the SDR kits VFO I have, It results in a Dead BITX-40 .. No RX no TX . On Wed, 8 Feb 2017 at 17:41, Lawrence Macionski via Groups.Io QUOTE- "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".
Then if that is true then setting the VFO frequency to 19Mhz? (19-12=7) will invert- (USB) for 7Mhz? Then enabling Digital modes?? Something the Raduino could do? Advise.... de W8LM -KANSAS
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USB is already in the Raduino software, just not implemented.
--
Rob G4NQX
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That's not a 26mhz "offset". ? You want zero offset, set the VFO for 26 mhz going out. I have no idea if your VFO can emit 26mhz. If that fails, you could return the VFO to 5mhz as it was, and add a variable cap at C103 to bring down the frequency by 3khz or so. ?Not sure how much capacitance would be required, I assume well under 100pf. ?
On Wed, Feb 8, 2017 at 10:14 am, Marc Jones wrote:
Offset set to 26.000 MHz results in a dead BITX-40. ?
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I've tried using a 19.0 MHz IF from the SDR kits VFO I have, It results in a Dead BITX-40 .. No RX no TX .
On Wed, 8 Feb 2017 at 17:41, Lawrence Macionski via Groups.Io <am_fm_radio@...> wrote: QUOTE- "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".
Then if that is true then setting the VFO frequency to 19Mhz? (19-12=7) will invert- (USB) for 7Mhz? Then enabling Digital modes?? Something the Raduino could do? Advise.... de W8LM -KANSAS
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Offset set to 26.000 MHz results in a dead BITX-40... No RX, No TX ... I'm really not getting anywhere with this SDR kits VFO.. I've tried Putting in numerous frequencies for the IF , ?None result in ?a 7 MHz Frequency that is on LSB .?
On Wed, 8 Feb 2017 at 17:41, Lawrence Macionski via Groups.Io <am_fm_radio@...> wrote: QUOTE- "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".
Then if that is true then setting the VFO frequency to 19Mhz? (19-12=7) will invert- (USB) for 7Mhz? Then enabling Digital modes?? Something the Raduino could do? Advise.... de W8LM -KANSAS
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Should read: ? ?assuming you can easily set that VFO to 19mhz.
On Wed, Feb 8, 2017 at 10:12 am, Jerry Gaffke wrote:
assuming you can easily set that VFO to 26mhz. ?
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Yes, a 19mhz vfo will move a Bitx40 from LSB to USB. ?And your simplest solution, assuming you can easily set that VFO to 26mhz. ?Should just work. Another way is to drive the BFO from a spare Si5351 channel so you can move the carrier down few khz to where the filter lets through the upper sideband, leave the VFO where it's at. ?A somewhat more intuitive approach, and allows the BFO to be centered in the crystal filter passband for debug or CW. ?Requires a change to the Raduino code, and a wire from the Si5351 into the BFO, but I think eventually this is the best way forward. Jerry
On Wed, Feb 8, 2017 at 09:41 am, Lawrence Macionski wrote: setting the VFO frequency to 19Mhz? (19-12=7) will invert- (USB) for 7Mhz? ?
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QUOTE- "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".
Then if that is true then setting the VFO frequency to 19Mhz? (19-12=7) will invert- (USB) for 7Mhz? Then enabling Digital modes?? Something the Raduino could do? Advise.... de W8LM -KANSAS
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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.
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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.
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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
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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
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
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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
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Just to let you all know that the latest Tips n Mods is in the first folder in the Files section.
--
Rob G4NQX
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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
toggle quoted message
Show quoted text
At 08/02/2017, you wrote: 1st contact, 6 feet, work bench to work bench. Sounded good.
Ed
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Reading this file about the LM386 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.
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Re: New BITX40 on the air.
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
?
?
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Marc Jones
Raj vu2zap