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On TX Bandpass filter
With three CPU lines and shift registers you could operate as many relays as you need. An you can get a chip that is a shift register and relay driver in one, the TPIC6B595. To get the full value of t
With three CPU lines and shift registers you could operate as many relays as you need. An you can get a chip that is a shift register and relay driver in one, the TPIC6B595. To get the full value of t
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Clark Martin
· #82574
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100W Automatic Antenna Tuner...
Watch for whether the MCU is pre-programmed. Mine was and the e-bay page said so but some are not. I haven’t seen any programming interface on the board but I’m not familiar with PIC programming (one
Watch for whether the MCU is pre-programmed. Mine was and the e-bay page said so but some are not. I haven’t seen any programming interface on the board but I’m not familiar with PIC programming (one
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Clark Martin
· #82236
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Replacing SMD component
For SMD I’ve found the following helpful. Headset magnifier fine tweezers practice Both with a conventional soldering iron and my hot air rework station, I practiced on desoldering components till I g
For SMD I’ve found the following helpful. Headset magnifier fine tweezers practice Both with a conventional soldering iron and my hot air rework station, I practiced on desoldering components till I g
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Clark Martin
· #81860
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Relay for antenna tuner output?
Use the some model of relay as in the antenna tuner. If it isn’t adequate, the tuner is in trouble. Clark Martin KK6ISP
Use the some model of relay as in the antenna tuner. If it isn’t adequate, the tuner is in trouble. Clark Martin KK6ISP
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By
Clark Martin
· #81384
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#v3 #ubitx #ubitx-help
#v3
#ubitx
#ubitx-help
Check the relays. If it’s in all bands then check the T/R relay, if it’s just some bands, check the filter relays. In either case bad relay contacts would account for both problems. Sent from an iPhon
Check the relays. If it’s in all bands then check the T/R relay, if it’s just some bands, check the filter relays. In either case bad relay contacts would account for both problems. Sent from an iPhon
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Clark Martin
· #78813
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Off topic question
Check the numbers for maximum charging current to the battery and make sure your panel doesn’t exceed it. A few charge controllers let you set a maximum charge current but most don’t. Clark Martin KK6
Check the numbers for maximum charging current to the battery and make sure your panel doesn’t exceed it. A few charge controllers let you set a maximum charge current but most don’t. Clark Martin KK6
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By
Clark Martin
· #78140
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Overvoltage spike killed my V4
If you have a variable voltage supply use that while monitoring the current to slowly increase the supply voltage until the current gets up to around 200 mA. Then start probing see where the current i
If you have a variable voltage supply use that while monitoring the current to slowly increase the supply voltage until the current gets up to around 200 mA. Then start probing see where the current i
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By
Clark Martin
· #75575
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uBITX V6 heat sink temperature
Cheap replacement unless it’s failure mode is to send Vin to Vout, then… ouch. Clark Martin KK6ISP
Cheap replacement unless it’s failure mode is to send Vin to Vout, then… ouch. Clark Martin KK6ISP
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By
Clark Martin
· #74523
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How to get rid of Local FM broadcast stations
#ubitx
To verify, if you have a low power transmitter (oscillator) that can tune around the offending AM BCB frequency, turn it on near the µBitX and see if you can interfere with the interfering signal. If
To verify, if you have a low power transmitter (oscillator) that can tune around the offending AM BCB frequency, turn it on near the µBitX and see if you can interfere with the interfering signal. If
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Clark Martin
· #73990
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#ubitx
#ubitx
hex files are executable images, i.e. you don’t compile them, they’ve already been compiled and linked. To download it to the arduino you need to use avrdude directly. Something like: avrdude -p atmeg
hex files are executable images, i.e. you don’t compile them, they’ve already been compiled and linked. To download it to the arduino you need to use avrdude directly. Something like: avrdude -p atmeg
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Clark Martin
· #73310
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Adjusting pa bias (RV3) blows one of the final
#ubitx
It’s the black wire connected to the black terminal. It just has a strip of red from where it separated from the red wire. Clark Martin KK6ISP
It’s the black wire connected to the black terminal. It just has a strip of red from where it separated from the red wire. Clark Martin KK6ISP
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By
Clark Martin
· #73215
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"Steal" T/R from Raduino pin 16?
No need to “steal”, you can just “use" it.:) Yes, one MCU’s outputs can certainly be another MCU’s input. No resistor or pull up or down is needed, the output is driven high or low. Any MCU’s input is
No need to “steal”, you can just “use" it.:) Yes, one MCU’s outputs can certainly be another MCU’s input. No resistor or pull up or down is needed, the output is driven high or low. Any MCU’s input is
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By
Clark Martin
· #72593
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Reset Raduino - How
One of my goto tools is a logic probe. It’s 30-40 years old, the LEDs are a little hard to read at times but it still works great. It would quickly diagnose a problem like this by testing each pin of
One of my goto tools is a logic probe. It’s 30-40 years old, the LEDs are a little hard to read at times but it still works great. It would quickly diagnose a problem like this by testing each pin of
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By
Clark Martin
· #72507
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Nearly non-existent output power, no mod
Additionally, for the SSB tests what was the AF signal source? Clark Martin KK6ISP
Additionally, for the SSB tests what was the AF signal source? Clark Martin KK6ISP
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By
Clark Martin
· #71946
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Nearly non-existent output power, no mod
Sorry, but you description below is akin to bad driving directions… (turn right at the green house, etc). It would be far easier and more accurate to specify where the signal was measured (and how). i
Sorry, but you description below is akin to bad driving directions… (turn right at the green house, etc). It would be far easier and more accurate to specify where the signal was measured (and how). i
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By
Clark Martin
· #71945
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Nearly non-existent output power, no mod
Use an RF probe or oscilloscope to trace the signal through the relays / filters. Clark Martin KK6ISP
Use an RF probe or oscilloscope to trace the signal through the relays / filters. Clark Martin KK6ISP
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By
Clark Martin
· #71870
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New wiring diagram version
Except that you’ll have voltage across the PA V+ and main V+. If the PA V+ is actually negative the parasitic diode in the final transistors will conduct and you’ll have reverse voltage to the main V+
Except that you’ll have voltage across the PA V+ and main V+. If the PA V+ is actually negative the parasitic diode in the final transistors will conduct and you’ll have reverse voltage to the main V+
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By
Clark Martin
· #71701
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ubitx calibration
Years ago I zero beat (although I didn’t call it that) an NE555 running at 60Hz to the AC line by connecting an analog voltmeter between them. As it neared zero beat the meter started swinging back an
Years ago I zero beat (although I didn’t call it that) an NE555 running at 60Hz to the AC line by connecting an analog voltmeter between them. As it neared zero beat the meter started swinging back an
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By
Clark Martin
· #70925
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uBITX finals get hot very fast
#ubitx-help
#ubitx
#v5
What is the idle current into the PA with the mic PTT pressed (or the equivalent)? It should be 400 mA max. That’s measuring the power just into the PA section. The radio as a whole should be 500mA ma
What is the idle current into the PA with the mic PTT pressed (or the equivalent)? It should be 400 mA max. That’s measuring the power just into the PA section. The radio as a whole should be 500mA ma
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By
Clark Martin
· #70759
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Newby - uBitx powers on but no Rx
If you are in or near the US, try tuning in WWV on any of it’s frequencies. Clark Martin KK6ISP
If you are in or near the US, try tuning in WWV on any of it’s frequencies. Clark Martin KK6ISP
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By
Clark Martin
· #70248
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