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uBix - transmit clicking when Mic inserted

Jim Miller
 

Hello everyone,

I've sent several messages in the past asking about why my uBitx clicks (relay) as if it's trying to transmit when I connect a mic to the jack.  I've even sent some images of how I have it wired up and as best as I can tell I have it wired up correctly (search for previous posts).  I've also tried using the little button mic that comes with the kit and have the same issue.  

At this point, I don't know what else to do so I'm going to ask if there's an Elmer out there who'd be willing to be a 2nd pair of eyes and confirm that either there's an issue or I'm an idiot (the latter is more likely).  I'd be glad to pay shipping back and fourth (I'm in St.Louis, MO).

Thank you,
Jim Miller
AE0BZ

 

Jim,

If the mic connector is common with PTT then I suggest you try switching the PTT and mic contacts.

Raj

At 13-01-19, you wrote:
Hello everyone,

I've sent several messages in the past asking about why my uBitx clicks (relay) as if it's trying to transmit when I connect a mic to the jack. I've even sent some images of how I have it wired up and as best as I can tell I have it wired up correctly (search for previous posts). I've also tried using the little button mic that comes with the kit and have the same issue. Â

At this point, I don't know what else to do so I'm going to ask if there's an Elmer out there who'd be willing to be a 2nd pair of eyes and confirm that either there's an issue or I'm an idiot (the latter is more likely). I'd be glad to pay shipping back and fourth (I'm in St.Louis, MO).

Thank you,
Jim Miller
AE0BZ

_Dave_ K0MBT
 

That is what happens to all three of my ubitx radios. The work around that I have used is to not plug in mic when turned on.

Welcome from N.E. Mo.
73
Dave

Jack, W8TEE
 

Listen to see if the xmit relay is cycling. Take a paper towel tube and place it over each relay to determine if one is cycling. If so, look on the schematic to see what that relay controls.  If it's tied to the PTT circuit, the mic is probably wired incorrectly.

Jack, W8TEE

On Sunday, January 13, 2019, 10:21:41 AM EST, Jim Miller <stljim@...> wrote:


Hello everyone,

I've sent several messages in the past asking about why my uBitx clicks (relay) as if it's trying to transmit when I connect a mic to the jack.  I've even sent some images of how I have it wired up and as best as I can tell I have it wired up correctly (search for previous posts).  I've also tried using the little button mic that comes with the kit and have the same issue.  

At this point, I don't know what else to do so I'm going to ask if there's an Elmer out there who'd be willing to be a 2nd pair of eyes and confirm that either there's an issue or I'm an idiot (the latter is more likely).  I'd be glad to pay shipping back and fourth (I'm in St.Louis, MO).

Thank you,
Jim Miller
AE0BZ

Doug W
 

Do you have the keyer jack wired up?  If not do you have a 4.7k resistor between pins 2 and 3 of the radiuno?
--
www.bitxmap.com

Evan Hand
 

Jim,
I did go back and looked at your pictures, and from what I can see there it appears that you have wired the jacks correctly.  Can you send us pictures of how you have the plugs wired?  The external PTT switch is wired correctly, however to verify that it is working do you have an ohm meter to test that the switch does open and close?  It looks like you have the switch directly wired into the circuit, bypassing the mic/PTT jack.  That is OK, as long as it is working correctly.

Also, can you explain when you hear the relays clicking?  Is it when you turn the rig on with or without the mic plugged in?  Does it click only when you plug in the mic? Do the relays appear to drop out after clicking? Do they click when the PTT switch is pressed after the first click on insertion or power up?

To test without blowing your finals, only power the RED wire in the 3 wire power plug.  That is the Red positive 12v and black ground/the return of the 12v.  Do not power the brown wire.  You can then power and test the rig without actually transmitting.  The rest of the rig is powered up and can be used.  That should really be in the "startup" process, to make sure you have the receiver (and since the same VFOs are used) the transmitter aligned before going on the air.

FYI,
It is hard (at least for me) to give you accurate suggestions without getting very detailed information from you. If you can describe the actions and observations being clear on the order of occurrence, it helps me understand both what is going on as well as your understanding of what you are observing.  If this is viewed as condescending, I apologize.  I am simple minded, so often miss the obvious.

73
Evan
AC9TU

Gary Anderson
 

From the HF signals schematic and wire-up diagram (original V3 sourced in ~Feb/March 2018), it doesn't look like the designer anticipated that the Mic/PTT plug would be plugged-in after uBITX power-up.
I think this is where Raj is going when he suggests swapping PTT and Mic wires (on both the uBITX and your mic)

The original supplied V3 wire-up has:
Tip = "Mic" = 4.7K ohm resistor to TX (12V when in TX mode)
Ring = PTT = internal Nano pull-up to 5V
Sleeve = GND

When you plug in a TRS plug to the jack supplied in the kit, the Sleeve to Ring (jack side) can easily short if it is off on angle.
The internal springs in the jack help get the plug off angle  (at least on mine)
A short between PTT and GND puts the uBITX in TX mode.

As you continue to push in the plug, you short Tip to Ring on the jack. (You can see this through the clear plastic window on the jack)
For a brief moment if your uBITX went into TX mode, a second operating condition fault scenario:  4.7K Ohm pull-up to 12V on the Nano. 
Now you are depending on the ESD protection diodes internally to the Nano to protect from Electrical Over Stress.

Swapping Mic and PTT positions would seem to be more robust (I have not fully vetted this solution.)
You would still have the above Tip to Ring fault mode if you accidentally unplugged the while the uBITX was in TX mode.
(so not 100% robust, but that is much less likely to happen often enough to be of much concern, and if the Nano goes 'bad'; you have a clue)

Regards,
Gary




_Dave_ K0MBT
 

What is happening on my radio is that the tip shorts between the ground and the ptt as it slides in. Keying ptt. It shouldn't be putting out much power as the mic is not active until the last terminal is reached and engaged.

I try to not insert mic on running radio.

Bill Cromwell <wrcromwell@...>
 

Hi,

I don't plug-in or unlug anything wit the radio powered. Notthe uBitx. Not the PFR-3, not the Johnson Ranger, not the SW-3 (1933 vintage). Most of the time it's okay but can cause real fireworks. It's a habit that is good to promote.

73,

Bill KU8H

On 1/14/19 7:49 AM, d balfour wrote:
What is happening on my radio is that the tip shorts between the ground and the ptt as it slides in. Keying ptt. It shouldn't be putting out much power as the mic is not active until the last terminal is reached and engaged.
I try to not insert mic on running radio.
--
bark less - wag more