Re: dc power connection bitx40 confusion
Paul (call sign?) wrote... The post at /g/BITX20/message/23973 that Jerry pointed out pretty much says it all. Keep in mind that there are two places on the main circuit board that
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Keith VE7GDH
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#33005
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Re: Receiver Dead
audio preamp might be busted. the LM386 seems to be working (from the test that you performed). check the voltages around the audio preamp's base and collector. if the LM386 gives you noise, does the
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Ashhar Farhan
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#33004
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Re: BITX QSO Night, Sunday, October 1, 7pm Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Bump to top! -- John - WA2FZW
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John P <j.m.price@...>
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#33003
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Receiver Dead
When I first set up the Bitx40, it did seem to receive OK. ?Then there began to be various, random ¡°drop outs¡± into silence.? Cycling the power usually got it back.? Then one day it went dead
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Ken Macy <kmacy@...>
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#33002
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Re: PTT Sense Issues
From what I can tell, everything checks out OK. Voltage on A0 attached through 10k resistor to regulator output is ~1.22v RX, 5v TX. Regulator pin 1 is 0v RX, 5v TX. Regulator pin 3 is 0v RX, 12v TX.
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kg4usk@...
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#33001
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Re: W8TEE pending software release and port(?)
#w8tee
Check my photo album at the site, then. Jack, W8TEE To: [email protected] Sent: Sunday, October 1, 2017 1:59 PM Subject: Re: [BITX20] W8TEE pending software release and port(?) #w8tee Hi Jack, sorry
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Jack Purdum <jjpurdum@...>
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#33000
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Re: PTT Sense Issues
Allard, You are writing your firmware in such a way that users need not apply all mods. That might require a pullup or pulldown on A0, in which case it's best to ignore my previous post. If thresholds
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Jerry Gaffke
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#32999
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Re: W8TEE pending software release and port(?)
#w8tee
Hi Jack, sorry but my feedback is the same... no ?inline picture on the side. I am even logged in. TNT fer all . sTef DM5TU es 72/3`s
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sTef - DM5TU / VY1QRP
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#32998
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Re: PTT Sense Issues
Allard, What you have works well enough. But on the next rev of firmware, you might remove the pullup from A0. (As you are likely already planning to do.)
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Jerry Gaffke
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#32997
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Re: PTT Sense Issues
A0 should be approx 1.25V (LOW) during RX, 5V (HIGH) during TX. If this is not the case, first make sure that U3 is switching on and off correctly during RX/TX. U3 input pin 3 should be 12V during TX,
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Allard PE1NWL
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#32996
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Re: PTT Sense Issues
Yup, output of the 78L05 regulator should be zero volts when receiving, 5v when transmitting. It is powered from the TX rail of 12v, which is zero volts when receiving and 12v when transmitting Check
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Jerry Gaffke
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#32995
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Re: PTT Sense Issues
A0 and A1 both show 5v, PTT on and off. I don't have a key connected at the moment. I understand A1 is pulled low to send a carrier, but shouldn't A0 always be low until it sees 5v from the regulator?
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kg4usk@...
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#32994
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Re: PTT Sense Issues
What are the voltages on A0 and A1 if you measure them with a DVM? What voltages do you have when you press PPT or the CW key? 73 Allard PE1NWL
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Allard PE1NWL
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#32993
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Re: PTT Sense Issues
Thanks for getting back to me Allard. No shorts anywhere. I've done the reset and it does the same thing. There is nothing connected to the A1(KEY) wire. Do the CW Carrier and TX-RX connections need
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kg4usk@...
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#32992
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Re: W8TEE pending software release and port(?)
#w8tee
I think that a release that uses the same BITX40 board mods as Allard would be useful. When the new hardware comes in you can then upgrade to new features. ? Bob? KD8CGH
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Bob Benedict, KD8CGH
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#32991
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Re: W8TEE pending software release and port(?)
#w8tee
Ah, seems I wasn't signed in, somehow. Now found the photo. Nicely implemented, Jack. Bill, VK7MX
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Bill Maxwell
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#32990
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Re: W8TEE pending software release and port(?)
#w8tee
I posted the images to my W8TEE album. Jack, W8TEE To: [email protected] Sent: Saturday, September 30, 2017 6:26 PM Subject: Re: [BITX20] W8TEE pending software release and port(?) #w8tee Can't see the
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Jack Purdum <jjpurdum@...>
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#32989
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Re: PTT Sense Issues
The fact that your radio starts in CWL mode suggests that it sensed a key-down from the CW key. As a first step, please reset all user settings to "factory settings". Keep the FB pressed during power
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Allard PE1NWL
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#32988
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Re: PTT Sense Issues
Thanks for the replies. It seems like the Raduino thinks the radio is in TX mode - the radio itself is not transmitting. But, it does react to the PTT being activated. After initial power up it's in
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kg4usk@...
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#32987
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Re: PTT Sense Issues
Hi Luther It sounds like the radio thinks it's in TX mode when you turn it on. Is it actually in tx, or does the raduino just think it is? Brent VE3CUS
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Brent Seres/ VE3CUS
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#32986
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