Are you using screened enclosures for the ¦Ìbitx and tuner?
On Sun, Jul 1, 2018 at 4:14 PM, <davedt1e@...> wrote: Never mind for now.
It would appear that the problem now occurs without the tuner hooked up.? I've got some kind of mic or mic jack problem.? I guess it's just coincidence that it started when I hooked up the tuner.? Seems a little odd though.
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Re: RFI from uBitx TX after AGC and other mods installed
Also try putting a 100n directly across Q1 base-emitter on the AGC board. It will cut off some of the higher AF as it would be in series with C1 to earth across the Af gain control.?? However, this would not be of any serious consequences.
If you don't want as much AF HF cut off you can try a smaller capacitor, say 10n.
I am thinking that Q1 base-emitter junction is acting as a detector and the AF is being coupled back to the AF gain control since the level is varying with the AF Gain control. One could also add say a 10n capacitor directly on pin 7 of the TDA2822 or across the AF Gain control as an rf decoupling. Can you try and report?
On Sun, Jul 1, 2018 at 5:33 PM, Lawrence Galea <9h1avlaw@...> wrote: Did you put
100n, 10n, 1n
filter capacitors
?all in parallel on both input and output
directly across the 78L05 leads?
.
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Re: RFI from uBitx TX after AGC and other mods installed
Did you put
100n, 10n, 1n
filter capacitors
?all in parallel on both input and output
directly across the 78L05 leads?
.
On Sun, Jul 1, 2018 at 2:31 PM, Rick Price <rickprice48@...> wrote:
John, Don, others,
Yesterday I attached a 78L05 (TO220) directly to the back of
the AGC board that is mounted to the RF gain control on the front panel.
Bypassed all power leads and ran a separate power lead to the 12V regulator that
powers?my uBitx. In other words the AGC board had its own isolated(?) power
source. Stll heard the audio when transmitting.? Beginning to think that
radiated power is being absorbed by the AGC board and then recitifed and then
coupled into the audio system. I also have the pop click board installed and not
sure if this was a problem before it was installed. My AGC board is one I
fabricated using Don's technique of cutting pcb with an x-acto knife.? I
also have a AGC board made on perf board using through hole parts.? May sub
that in and see if there are any changes. I eventually plan on installing the
JackAl mod when it becomes available so this problem should go away for
me?but its beginning to become a challenge to fix.
?
Rick KN4AIE
Don,
I spent part of yesterday applying ferrites to this and that
to little success. I also tried wrapping the 5v line around the twisted pair
coming from the volume pot and that did some good. This morning I was thinking
about fixing a 7805 to the metal base of my case, drilling a hole in the ground
plane and routing a wire through that hole to feed the AGC board. It could be
driven off the 12v relay (K1?). Has anyone else had any
ideas/success?
John
KC9OJV
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Re: Anyone seen an SSB xmit causing the menu to pop up?
Quite a while ago I was messing with some Nano code, but had my FT-1200 on, too. I grabbed the mike and answered a CQ and I remember the Nano display changing when I activated the mic. It turns out that the coax to the antenna switch passed within inches of the Nano. I put two ferrite beads on the coax and it didn't happen again. FWIW.
Jack, W8TEE
On Sunday, July 1, 2018, 11:15:07 AM EDT, Gwen Patton <ardrhi@...> wrote:
I'm running on a different battery than the jump box I was using before. It should have sufficient amperage. I'll test it with my bench supply and see if it does it under those conditions. It's odd, though, I was running my bench supply in current limit mode at 1.5 and 2 amps, and it didn't exhibit this behavior. It almost seemed like the RF was getting into the Nano and triggering the menu event for some reason. Very peculiar.
It behaves precisely as if I pushed the encoder knob in to operate the menu switch. I key the mike, speak loudly into it or whistle into it, and BAM, the radio goes into menu mode and receive stops. I can get out of it by pushing the knob twice to cycle band select mode, but it's annoying. I was just wondering if someone else spotted this behavior and added ferrites or some other solution. I'll keep fiddling with it.
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Re: Anyone seen an SSB xmit causing the menu to pop up?
I'm running on a different battery than the jump box I was using before. It should have sufficient amperage. I'll test it with my bench supply and see if it does it under those conditions. It's odd, though, I was running my bench supply in current limit mode at 1.5 and 2 amps, and it didn't exhibit this behavior. It almost seemed like the RF was getting into the Nano and triggering the menu event for some reason. Very peculiar.
It behaves precisely as if I pushed the encoder knob in to operate the menu switch. I key the mike, speak loudly into it or whistle into it, and BAM, the radio goes into menu mode and receive stops. I can get out of it by pushing the knob twice to cycle band select mode, but it's annoying. I was just wondering if someone else spotted this behavior and added ferrites or some other solution. I'll keep fiddling with it.
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Re: RFI from uBitx TX after AGC and other mods installed
I think it would be eaiser to shield the little pcb with foil
before moving it due to the interconnect wires.? May try that first as the
pcb is very small and mounted to the back of the RF Gain pot. The PCB is
fabircated like Don explained in his first description of the board. My PCB is
not the Kee's kit. I'll let you know how the shielding works
out.
Rick
KN4AIE
toggle quoted message
Show quoted text
Rick, If it's the PCB what about putting it below the ground plane in
the same relative position as the suggested spot next to the RF
relays? John KC9OJV
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Never mind for now.
It would appear that the problem now occurs without the tuner hooked up.? I've got some kind of mic or mic jack problem.? I guess it's just coincidence that it started when I hooked up the tuner.? Seems a little odd though.
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Yes, I have seen similar phenomena. In
my case my CW wires to my key were too close to my 50 watt linear.
Your tuner is probably radiating a lot of RF.
Howard
On 7/1/2018 9:24 AM, davedt1e@... wrote:
toggle quoted message
Show quoted text
Hope this is an
appropriate topic for the board.
Just built he QRP Guys Multi Z tuner and hooked it up to the
Ubitx.? The Ubitx goes straight into TX on power up.? I was very
careful in building the tuner and don't think I made any
errors.
The antenna is a horizontal loop cut a bit over 40 meters and fed
with ladder line.
The Ubitx behaves normally when using a dummy load or with loop
hooked up for receive.
No balun is currently attached.
Any ideas as to what's happening?
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Re: Bitx40 75KHz Spurious, How to solve it.
#bitx40
Correction 500KHz span!
toggle quoted message
Show quoted text
At 01-07-18, you wrote: Akira,
I just put my uBitxr4 on the spectrum analyzer and found nothing +-250 Khz. That is 500 Khz BW.
I think your measurements are being affected by switch mode power supply in one of the items.
Raj
At 25-06-18, you wrote:
Hi!
I built Bitx40 about 2 weeks ago.
I measured the spurious of Bitx40 by using the spectrum analyzer.
The level of spurious of harmonics were under 50db. So this is fine.
But the spurious at 75KHz was observed.
The spurious might be the multiple of 25KHz.
It would be much appreciated if you could advise me the cause and solution of this spurious of Bitx40.
In Japan, we must prove to the authority that the spurious of the transceiver meets the criteria to obtain the certification of the transceiver from the authority.
So if i could not resolve this spurious, I will not be able to use Bitx40 in Japan.
Thanks in advance,
Akira
JJ1EPE
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Re: Anyone seen an SSB xmit causing the menu to pop up?
Hi Gwen, I had something similar on both SSB & CW.? Part of my problem was my 3amp laptop power supply was shutting down.? It reset the radio.? I got a 5 amp power supply to fix that issue.? After that, I had display issues, like you are describing.? I seemed to lock up the nano.? The screen would be on and the radio would transmit but the screen was blank and it would not go back to receive.? I fixed this by putting a clip on ferrite over all the wires coming from the Raduino.?? Interestingly, it only happened on 20M.? That is where my radio seems to have the best power efficiency.? I was using a 50 ohm dummy load when I was having these issues.??
Hope this helps.
Marco - KG5PRT?
On Sun, Jul 1, 2018, 7:43 AM Mvs Sarma < mvssarma@...> wrote: learnt a point Farhan jee.
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Re: Bitx40 75KHz Spurious, How to solve it.
#bitx40
Akira,
I just put my uBitxr4 on the spectrum analyzer and found nothing +-250 Khz. That is 500 Khz BW.
I think your measurements are being affected by switch mode power supply in one of the items.
Raj
toggle quoted message
Show quoted text
At 25-06-18, you wrote: Hi!
I built Bitx40 about 2 weeks ago.
I measured the spurious of Bitx40 by using the spectrum analyzer.
The level of spurious of harmonics were under 50db. So this is fine.
But the spurious at 75KHz was observed.
The spurious might be the multiple of 25KHz.
It would be much appreciated if you could advise me the cause and solution of this spurious of Bitx40.
In Japan, we must prove to the authority that the spurious of the transceiver meets the criteria to obtain the certification of the transceiver from the authority.
So if i could not resolve this spurious, I will not be able to use Bitx40 in Japan.
Thanks in advance,
Akira
JJ1EPE
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Re: RFI from uBitx TX after AGC and other mods installed
Rick, If it's the PCB what about putting it below the ground plane in the same relative position as the suggested spot next to the RF relays?
John
KC9OJV
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Hope this is an appropriate topic for the board.
Just built he QRP Guys Multi Z tuner and hooked it up to the Ubitx.? The Ubitx goes straight into TX on power up.? I was very careful in building the tuner and don't think I made any errors.
The antenna is a horizontal loop cut a bit over 40 meters and fed with ladder line.
The Ubitx behaves normally when using a dummy load or with loop hooked up for receive.
No balun is currently attached.
Any ideas as to what's happening?
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let someone from the competent radio engineers check my method and tell here for everyone if it works.
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Richard, good afternoon!
note, there are many people here who consider themselves radio engineers. but no one gives you advice on calibration.
I'll try with my bad English to tell you how to properly calibrate. for this, it is tedious to measure and record the true value of the BFO frequency in the file. for this you need: a commercial transceiver (I have FT-2000), an Android smartphone and an installed program Audio Frequency Counter (?or any similar),?piece of wire. the transceivers warm up for 30 minutes. in the commercial transceiver we set 25.000.00 and usb. Instead of the antenna, we connect a piece of wire and bring it close to the raduino.?a commercial transceiver we find a raduino tone. for example: i have 25.003 50. next the smartphone will measure the frequency of AUDIO speaker.? for example: freq in transceiver 25.003.500, audio freq 902 Hz. 25.003.500+902=25.004.402?this is the true frequency BFO you uBitx!!!? this frequency must be written in the firmware file name ubitx_si5351.ino for example: here are my changes ? ? ?#define SI5351BX_XTAL 25004402 ? ? ? ? ?// Crystal freq in Hz? this should be done with the help of the program arduino ide.? how to do it (and it's very simple) let him tell someone from the engineers who speak English better than me.
After that, the tuning and calibration of the transceiver will take several minutes.
good luck!
?
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Re: Nextion Display programming, extension cable
That looks neat..
--
Allen ?Merrell
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Re: TX frequency? of uBitx at CWL and CWU mode
#ubitxcw
Akira-san :?
The uBITX display frequency in CWU/CWL is the RX frequency not the TX frequency. The norm in CW on most commercial rigs is to always display the TX frequency.
You can however set the RX offset. It seems that yours must be 1.5 Khz which is a lot. Typically it would be something in the range of 500 to 800 Hz.?
There is a related issue which I have reported and that is that changing CW modes is "broken". When switching back and?
forth between CWU/CWL modes the TX frequency changes and the RX frequency does not which is wrong. This means that?
if you properly tune in a CW station (RX tone matches your offset) on CWU and switch to CWL the other station is no longer audible and?
he can't hear you. It should be possible to switch back and forth between CWU and CWL and still maintain contact.
See message #51983 for more details.
Cheers
Michael VE3WMB?
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Re: Bitx (40) agc and muting
from junction r111/r113 solder a 1n4148 diode direct to the 12volt rail
(LM368 is now alltime connected with 12volt)
73 elmar-dl2qa
?
Gesendet:?Sonntag, 01. Juli 2018 um 14:15 Uhr
Von:?4Z1NT <menashedovid@...>
An:[email protected]
Betreff:?Re: [BITX20] Bitx (40) agc and muting
When you say solder 1n4148 t0 +12v not RX, which one are we talking about?
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Re: RFI from uBitx TX after AGC and other mods installed
John, Don, others,
Yesterday I attached a 78L05 (TO220) directly to the back of
the AGC board that is mounted to the RF gain control on the front panel.
Bypassed all power leads and ran a separate power lead to the 12V regulator that
powers?my uBitx. In other words the AGC board had its own isolated(?) power
source. Stll heard the audio when transmitting.? Beginning to think that
radiated power is being absorbed by the AGC board and then recitifed and then
coupled into the audio system. I also have the pop click board installed and not
sure if this was a problem before it was installed. My AGC board is one I
fabricated using Don's technique of cutting pcb with an x-acto knife.? I
also have a AGC board made on perf board using through hole parts.? May sub
that in and see if there are any changes. I eventually plan on installing the
JackAl mod when it becomes available so this problem should go away for
me?but its beginning to become a challenge to fix.
?
Rick KN4AIE
toggle quoted message
Show quoted text
Don, I spent part of yesterday applying ferrites to this and that
to little success. I also tried wrapping the 5v line around the twisted pair
coming from the volume pot and that did some good. This morning I was thinking
about fixing a 7805 to the metal base of my case, drilling a hole in the ground
plane and routing a wire through that hole to feed the AGC board. It could be
driven off the 12v relay (K1?). Has anyone else had any
ideas/success? John KC9OJV
|
Gwen Patton
Raj vu2zap