CW Mode Operation

A65BK
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CW Mode Operation

Postby A65BK » Sun Dec 24, 2017 6:57 am

Hi Team,

I have been facing a trouble while using my Hermes board. When I select CW mode, the Radio switch immediately to TX mode, as if we pressed MOX button. I have not connected any key to radio !

Please advise me if it is any setting issue here ?/

73s

Prem
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w-u-2-o
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Re: CW Mode Operation

Postby w-u-2-o » Sun Dec 24, 2017 12:22 pm

Prem,

If this is on your homebrew board then please consider that you may have a hardware short circuit on the key input path.

73,

Scott
A65BK
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Re: CW Mode Operation

Postby A65BK » Sun Dec 24, 2017 12:43 pm

Hi Scott,

Yes, it is on my HB Hermes.
Any suggestion to find faulty point ?
Without key, what shall be the signal at U25 Dot and Dash Pins ?? At low or hi ??
Do you expect a short from Dash to ground ? In that case, we need to get continuous Dash !! I get my TX in MOX mode without any break in signal !!

73s

Prem
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w-u-2-o
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Re: CW Mode Operation

Postby w-u-2-o » Sun Dec 24, 2017 4:36 pm

Prem,

The schematic clearly shows that the CW_DOT and CW_DASH signals are pulled up to 3.3V, and that the intent at J6 is that asserting a DOT or a DASH is accomplished by grounding the relevant line.

If you look at the data sheet for U25 you will see that it is a non-inverting buffer, and therefore you should see +3.3V at both FPGA pins 76 and 73 if nothing is shorted to ground somewhere. If you see 0V at either FPGA pin, then you need to trace back and inspect to determine where the signal is becoming shorted. This could be at the FPGA, U25, FL16, FL17 or J6, and possibly even R121 or R130.

Please don't ask me where I think it is. I'd need to have the board in front of me and an oscilloscope to tell you. You will have to do the physical debugging.

73,

Scott
K9RX
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Re: CW Mode Operation

Postby K9RX » Sun Dec 24, 2017 8:46 pm

not sure why the suggestion is or the focus went to the dot or dash lines - if they were pulled down then the radio would be producing dots or dashes! My understanding is that it is just going to TX period, "as if we pressed MOX button" ... if these lines go directly to the FPGA (whether through buffering or not) they wouldn't be the culprit for this fault description... I'd check PTT in .... I don't remember if there is some interplay with the mode vs. PTT but there's little else that should force it to TX continuous - VOX?

Gary
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Re: CW Mode Operation

Postby A65BK » Tue Jan 09, 2018 6:01 pm

Hi Scott, Gary

Thanks for reply. As Gary mentioned, I don't get a continuous DOT or DASH !!

So it can be something else than a short to ground. Is it ?

Please see the screen shot when I select CW mode. It switch to "MOX" not "TUNE". But . still I get same output power as if TUNE is pressed !!

Please advise further.

73s

Prem.
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w-u-2-o
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Re: CW Mode Operation

Postby w-u-2-o » Tue Jan 09, 2018 10:54 pm

I have no clue what could cause that.
K9RX
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Re: CW Mode Operation

Postby K9RX » Wed Jan 10, 2018 3:41 pm

As a starter I find odd things like this need to be done by wholesale changes ... so what I'd do is this:
-go back to USB
-set the frequency to 14050
-turn off the noise abatement stuff - everything off.
-click the "imabic" button
-click the breakin button
-click the sidetone
-CTUN off
-RX1 APF to a gain of 1
-CW speed to 25

go to CAT panel, make sure the PTT check box (enable) is unchecked for now.

[I've found a couple of really odd non-connected issues so 'common sense' doesn't necessarily apply here...]

after doing all this - then try changing the mode to CWU.

See what that does ... probably no change but I'd at least start from this position.

Gary
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A65BK
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Re: CW Mode Operation

Postby A65BK » Wed Jan 10, 2018 5:28 pm

Hi Gary,

Some of the points in your procedure was confusing to me and I have done as I could understand. Please have a look at the video prepared to see how my Hermes behave with CW mode.

Please help me further.

http://www.youtube.com/watch?v=INP6dfVNSbk

Rds,

Prem
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Re: CW Mode Operation

Postby K9RX » Wed Jan 10, 2018 9:48 pm

Prem,

Ok - looking at the power meter it does look like it is transmitting something other than a pure carrier - it looks like it is turning on and off ... and you have nothing connected to the CW jack on the rig? It almost looks like it is alternating between dits and dahs which is what it would do if BOTH of these inputs were grounded ...

also go to DSP | CW ... under "Connectors" it should say "Radio" and "none" .... if not change it to this and see if that helps.

Gary
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Re: CW Mode Operation

Postby w-u-2-o » Wed Jan 10, 2018 10:48 pm

Looks like one of the keylines is shorted to me, just like I typed above a while ago.
K9RX
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Re: CW Mode Operation

Postby K9RX » Wed Jan 10, 2018 11:35 pm

yeah - unfortunately the description didn't warrany the remedy at the time - stuck line ... it was described as

"I get my TX in MOX mode without any break in signal !!"

...but now looking at the VIDEO (not a jpg) it is apparent that something is 'stuck' ... and you can see the waveform appears to be more than "a stuck line" at a constant rate but rather the power meter is blinking at different rates - thus TWO stuck lines!

Gary
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Re: CW Mode Operation

Postby K9RX » Wed Jan 10, 2018 11:43 pm

as a side note look at the rate of what appears to be the imabic keying (dit/dah when both on) ... it is slow - I had to go back through the video to confirm - he did have the original jpg showing 40 WPM and I had suggested he reduce that - and sure enough its set at 6 WPM in the video!

Prem,

My guess is that if you changed the WPM speed you'll see the meter movement, what seems clear to be a dit and a dah, speed up ...

so ... it is unlikely that BOTH lines are somehow stuck on the board ... so I'd still suspect a setting causing it. That stated you can check the buffer pins 17 and 16 of U25 .... if they're both low check 3 and 4 to see if they're also low ...


Gary
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Re: CW Mode Operation

Postby A65BK » Thu Jan 11, 2018 8:45 am

Hi Gary and Scott,

Before opening my Hermes box for voltage test, I made one more short video to show you what happens if I switch off Lambic keyer option.
The meter swing stops now.
Earlier in my DSP- CW - Connections : Both were none. I changed first one to Radio, as you advised. Video was taken after this change.

http://www.youtube.com/watch?v=umRiGPIvBkc

73s

Prem
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Re: CW Mode Operation

Postby w-u-2-o » Thu Jan 11, 2018 10:56 am

Still think it is a short on on of the key lines.
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Re: CW Mode Operation

Postby K9RX » Thu Jan 11, 2018 2:13 pm

Prem..... its obvious it is being keyed - check U25. I'd HOPE that it isn't hardware as hardware should be more reliable... (its what I do for a living - Hardware/software development and design) if this is a new board... but things can happen ... but at this stage you need to check the chip to rule it out or to determine if indeed it is the cause.

If I recall Scott had said the IC number was the same (I only have the Orion II/8000 schematics) ... for the OII the pins are 3 and 4 for the input to the buffer, 16 and 17 for the outputs.

Gary
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A65BK
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Re: CW Mode Operation

Postby A65BK » Thu Jan 11, 2018 3:41 pm

Hi Scott & Gary,

I refered back to my schematic dwg print which I was using during my Hermes aseembly and testing. There I have recorded the voltages at U25 Pins : 3,4 which are Dot and Dash key in points . Also Pins : 16 & 17 which are out from U25 . These out pins go to FPGA Pins. I had 3.3V on all the Pins, without connecting Key.

Is this normal or U25 need replacement ?
What we expect at FPGA Pins without key ? 3.3V or 0V ??

How is normal working for CWL/CWU ?? Only when key is pressed (Dit or Dash) the Hermes need to switch to MOX ??

Please advise further.

73s

Prem
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Re: CW Mode Operation

Postby AB2EZ » Thu Jan 11, 2018 7:35 pm

Prem

The data sheet for U25 is readily available on-line. The truth table is included in the data sheets.

With both the dot and dash inputs in key up position (I.e. Not shorted to ground, and therefore both measuring 3.3V to ground), the dot and dash output pins should also bothmeasure 3.3V to ground.

Therefore, U25 appears to be working as it should.

Just to further confirm... insert a key, and test the dot and dash key down output voltages. For both dot and dash, key down should produce a low voltage to ground at the corresponding output.

The problem is (in my opinion) probably a corrupt firmware load (reinstall the latest firmware).

Stu
A65BK
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Re: CW Mode Operation

Postby A65BK » Fri Jan 12, 2018 10:37 am

Hi Stu,
I had refreshed the Firmware more than one time during earlier testing.
I tried connecting (shorting Key points or Pins), no change visible in screen. I did not open to check the voltage. Will do that.
can you let me know the real working during CW mode ?

Will the Radio go to TX (MOX ON) mode, if we switch to CW ?
or else Radio will move to MOX only when we press CW key ?? (as in all conventional Rigs ?)

73s

Prem
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Re: CW Mode Operation

Postby K9RX » Fri Jan 12, 2018 2:07 pm

As I suspected - hardware very rarely fails. So its not the buffer. There is some weird state - something programmed that has a bearing on it. Note that it doesn't have to make sense. There was an issue in an earlier version when I first started using the program where there was a parameter called "All Mode PTT" ... I found that if it were unchecked (default was checked) that on ... I'm trying to remember ... when you transmitted on CW it would show a "RX" level on the TX meter (dbm) even with FWD PWR selected and the power out would be very low ... if you then transmitted on TUN or SSB it would fix the power out problem but not the meter issue. This was repeatable with other radios. I had reported it and lo-n-behold it 'disappeared' as a parameter in a later version (it served little purpose any way). So there can be settings that have a weird non-intended knock on effect.

Let me look at the parameters ... then we can compare and see what is what.

Note although again with 40 years of experience I can say that hardware indeed rarely fails the fact of the matter is it can - so it might be the FPGA itself ... you might need to send it in for service.

Gary
K9RX
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Re: CW Mode Operation

Postby AB2EZ » Fri Jan 12, 2018 2:08 pm

Prem

In CW mode, the radio (if operating as designed) will only switch to transmit (MOX button illuminated) if the dot or dash key contact is closed (or if both are closed simultaneously.

In iambic mode ... closing both the key contacts simultaneously will produce an output which is an alternating pattern of dots and dashes.

Stu
K9RX
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Re: CW Mode Operation

Postby K9RX » Fri Jan 12, 2018 2:40 pm

Stu,

I pointed that out a few days ago - that we're seeing the results of "iambic" action ... but its clear it isn't going in ... or at least as measured coming out of the buffer since both dit and dah are high. I distinguish between coming out of the buffer vs. going in to the FPGA simply because it wasn't measured at that point on the board - its possible - although extremely improbable that both lines are unconnected at the FPGA ... but even then more than likely there are weak internal pullups which would still keep it in an unkeyed state. I think this has to be in software - some weird interaction with parameters.

Gary
A65BK
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Re: CW Mode Operation

Postby A65BK » Sat Jan 13, 2018 12:31 pm

Hi Friends,

After a detailed troubleshooting opening the box on my Hermes board, I could notice that one CW line pin on U9 had a dry soldering and which was the trouble for my CW faulty MOX .
I corrected dry soldering and now , only if I short either Key point to ground only it switch to MOX. I am not a CW operator and so don't know much.
Where can I get the details to understand
Lambic
Side tone
Semi breakin functions ?

If I short Dit or Dash line to ground, I need to get continuous Dit or Dash . Is it ?? I dont see it.
Any other setting missing for me ?

Thank you all for advising and helping me to clear my Hardware fault.

73s

Prem, A65BK
K9RX
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Re: CW Mode Operation

Postby K9RX » Sat Jan 13, 2018 2:08 pm

Prem,

Super - congrats! I had a poor solder connection on one of the caps on my Orion II board as well ...

As for setting it up - assuming you are using an iambic paddle you will want to turn it on - if you're new I'd suggest you use "semi-breakin" by checking that box and setting it to about 100mS (I use less than this but for slower code this is ok). Then set your speed ... note I found that one timing setting is crucial, at least on the OII board/system in the 8000. That is the General | Options | CW Delay Keydown. I found that with settings less than 7 I get SWR warnings. With a value of 4 it shows really high SWR! I have it set to 8.

Gary
K9RX
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Re: CW Mode Operation

Postby K9RX » Sat Jan 13, 2018 7:20 pm

Prem,

Can you tell me where exactly, IC and pin number that you found to be not soldered correctly? It seems odd that this happened on one connection since the key line is 2 lines, and you were obviously seeing iambic operation (both lines active) ... and if it were MOX related then you'd see it go to XMIT but not run the key lines! Seems odd.

Gary

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