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11. Potentiometer tuning for the Ultimate3


 

Hi Hans,
I added the U3S section 11. Potentiometer tuning for the Ultimate3?modifications to my v3.12 version but am getting problems. This is a U3S Transceiver using standard U3 Tx with relay switched LPFs and a standard Rx module with Polyphase board and 7MHz BPF fitted.

I have set Tn mode = 1 in the menu.

Problems are;
1) Upward frequency tuning only in Tx WSPR mode. I can hear clicking on my monitor Rx when the Tune pot is turned to min but the frequency does go lower.
2) In RX mode, upward movement of displayed frequency only, but it does not actually change the LO frequency (using 7mhz band). NO downward frequency either.
3) Loud clicking on Rx audio once pot is away from centre setting (in freq up or down positions)

I measure approx 0.5V on S1 with Tune pot at minimum, and approx 4.5V at max setting, and 2.5V in centre position.
Both S1 and S2 switches functioning ok.

I tried a complete 'RESET' and re-configured all my settings
I have used a 10k linear tune pot with 1k resistors.

Any ideas what may be wrong please.

73 Ken G4APB


 

¿ªÔÆÌåÓý

Hi Hans,

If you get a chance to consider the problems I mentioned earlier, here is some more data;

?

If I disable the Tune pot (Tn=0 in menu), and set the tune pot to anything lower than mid setting, the menu runs through as if switch S1 is pressed.

How do you programme for this conflict, is there a voltage level at which the A-D input on S1 decides whether it is a switch press or a minimum pot setting?

As I said, I measure approx 0.5V on S1 with Tune pot at minimum, and approx 4.5V at max setting, and 2.5V in centre position, so it is seeing less than 2.5V = switch pressed. I would have expected it to see anything above 0.5V as a pot setting only, and below that as a switch press.

?

FYI, I replaced the S2 switch with a combo push-pull switch/linear pot so I can still set the menu up, jam it on tx (ptt) for testing, AND have the tune pot all on the QRP labs case front panel. Was a mechanical nightmare to fit (is bigger than your rotary encoder), but looks good now. After so much effort I am keen to get this working.

73 Ken G4APB.

?

From: [email protected] [mailto:[email protected]] On Behalf Of KENS 2ND ACC via Groups.Io
Sent: 01 November 2017 17:07
To: [email protected]
Subject: [QRPLabs] 11. Potentiometer tuning for the Ultimate3

?

Hi Hans,
I added the U3S section 11. Potentiometer tuning for the Ultimate3?modifications to my v3.12 version but am getting problems. This is a U3S Transceiver using standard U3 Tx with relay switched LPFs and a standard Rx module with Polyphase board and 7MHz BPF fitted.

I have set Tn mode = 1 in the menu.

Problems are;
1) Upward frequency tuning only in Tx WSPR mode. I can hear clicking on my monitor Rx when the Tune pot is turned to min but the frequency does not go lower.
2) In RX mode, upward movement of displayed frequency only, but it does not actually change the LO frequency (using 7mhz band). NO downward frequency either.
3) Loud clicking on Rx audio once pot is away from centre setting (in freq up or down positions)

I measure approx 0.5V on S1 with Tune pot at minimum, and approx 4.5V at max setting, and 2.5V in centre position.
Both S1 and S2 switches functioning ok.

I tried a complete 'RESET' and re-configured all my settings
I have used a 10k linear tune pot with 1k resistors.

Any ideas what may be wrong please.

73 Ken G4APB


 

¿ªÔÆÌåÓý

Hi Hans,

I have been analysing this problem by setting my U3S to transmit the Analogue input channels 0-4 & 8 using the MESSAGE menu and TX CW mode. An undocumented feature I found is the actual analogue value is briefly shown on the display while it is being transmitted.

Results;

With Tn=0

CH0 = 1023 (Band 1 relay)

CH1 = 1017 (Switch S2)

CH2 =? 925 ¡®Switch S1/TUNE¡¯ pot at max, 511 pot at centre, can¡¯t measure below this as menu runs

CH3 = 1023 (Band 5 relay)

CH4 = 000 (pin 27)

CH8 = wide variation each time (internal temp) but around 290-350.

With Tn=1

CH2 = 556 pot in any position. (Menu run not affected).

?

BTW, ¡®CW¡¯ mode selected just jams the Tx on immediately and the only way out of this is a full RESET.

?

Hope this helps Hans.

?

73 Ken G4APB

?

From: [email protected] [mailto:[email protected]] On Behalf Of KENS 2ND ACC via Groups.Io
Sent: 02 November 2017 08:49
To: [email protected]
Subject: Re: [QRPLabs] 11. Potentiometer tuning for the Ultimate3

?

Hi Hans,

If you get a chance to consider the problems I mentioned earlier, here is some more data;

?

If I disable the Tune pot (Tn=0 in menu), and set the tune pot to anything lower than mid setting, the menu runs through as if switch S1 is pressed.

How do you programme for this conflict, is there a voltage level at which the A-D input on S1 decides whether it is a switch press or a minimum pot setting?

As I said, I measure approx 0.5V on S1 with Tune pot at minimum, and approx 4.5V at max setting, and 2.5V in centre position, so it is seeing less than 2.5V = switch pressed. I would have expected it to see anything above 0.5V as a pot setting only, and below that as a switch press.

?

FYI, I replaced the S2 switch with a combo push-pull switch/linear pot so I can still set the menu up, jam it on tx (ptt) for testing, AND have the tune pot all on the QRP labs case front panel. Was a mechanical nightmare to fit (is bigger than your rotary encoder), but looks good now. After so much effort I am keen to get this working.

73 Ken G4APB.

?

From: [email protected] [mailto:[email protected]] On Behalf Of KENS 2ND ACC via Groups.Io
Sent: 01 November 2017 17:07
To: [email protected]
Subject: [QRPLabs] 11. Potentiometer tuning for the Ultimate3

?

Hi Hans,
I added the U3S section 11. Potentiometer tuning for the Ultimate3?modifications to my v3.12 version but am getting problems. This is a U3S Transceiver using standard U3 Tx with relay switched LPFs and a standard Rx module with Polyphase board and 7MHz BPF fitted.

I have set Tn mode = 1 in the menu.

Problems are;
1) Upward frequency tuning only in Tx WSPR mode. I can hear clicking on my monitor Rx when the Tune pot is turned to min but the frequency does not go lower.
2) In RX mode, upward movement of displayed frequency only, but it does not actually change the LO frequency (using 7mhz band). NO downward frequency either.
3) Loud clicking on Rx audio once pot is away from centre setting (in freq up or down positions)

I measure approx 0.5V on S1 with Tune pot at minimum, and approx 4.5V at max setting, and 2.5V in centre position.
Both S1 and S2 switches functioning ok.

I tried a complete 'RESET' and re-configured all my settings
I have used a 10k linear tune pot with 1k resistors.

Any ideas what may be wrong please.

73 Ken G4APB


 

Gents, almost exactly the same problem here -? just boxed up my U3S and tried to add pot tuning. The freq only goes up, and control is very severe. I used a 4K7 pot and 470R resistors.

Any update on this would be great.

73 Steve MW0KST


 

I would also like to add the tuning pot to my U3S. Has this issue been addressed?

Thanks.

Glenn


 

Hi Glenn,
Hans has been strangely quiet on this. I was quite disappointed when v3.12a was released with no mention of this. I still have two now aging projects that have stalled because of this problem. Maybe it is a difficult one to fix, we will just have to be patient.

73
Ken G4APB


 

Not meaning to be quiet, Ken...

I just am a bit overloaded with work... the QCX stuff has been very busy, trying to speed up the backlog of orders etc. Things will calm down soon... and I can fix the potentiometer tuning thing in v3.13.?

73 Hans G0UPL

On Thu, Dec 21, 2017 at 10:17 AM, KENS 2ND ACC via Groups.Io <lfoofui.nbz42@...> wrote:
Hi Glenn,
Hans has been strangely quiet on this. I was quite disappointed when v3.12a was released with no mention of this. I still have two now aging projects that have stalled because of this problem. Maybe it is a difficult one to fix, we will just have to be patient.

73
Ken G4APB



 

OK Hans,
thanks for the update.
Merry Christmas and a Happy New year to to you and your elves.

73 Ken G4APB


 

Hi;

Any progress with this?. I'd like to order another U3S but I need the potentiometer option.

Thank you.

Glenn W2BX


 

Just a gentle reminder Hans. Any chance of fixing the Potentiometer TUNE problem? I have two projects stalled with v3.12a that are collecting dust.
73 Ken G4APB


 

Bump..... Waiting for this to be fixed...,,, any progress Hans?


 

Ok ok ok ok!

All you guys and your "gentle" reminders... Hans felt the pressure...?

This morning I have had the U3S on the bench and done some investigation in the code. I have found the reason why the tuning pot mod? only tunes in the UPWARDS direction. I have fixed it. It now tunes both ways.?

If you want me to email you this beta version .hex file which contains this correction, then please email me off-list.?

73 Hans G0UPL



On Mon, Feb 19, 2018 at 9:57 PM, fintronicsusa <fintronicsusa@...> wrote:
Bump..... Waiting for this to be fixed...,,, any progress Hans?



 

FYI... this new U3S version also does RTTY and JT4

On Tue, Feb 20, 2018 at 3:43 PM, Hans Summers <hans.summers@...> wrote:
Ok ok ok ok!

All you guys and your "gentle" reminders... Hans felt the pressure...?

This morning I have had the U3S on the bench and done some investigation in the code. I have found the reason why the tuning pot mod? only tunes in the UPWARDS direction. I have fixed it. It now tunes both ways.?

If you want me to email you this beta version .hex file which contains this correction, then please email me off-list.?

73 Hans G0UPL



On Mon, Feb 19, 2018 at 9:57 PM, fintronicsusa <fintronicsusa@...> wrote:
Bump..... Waiting for this to be fixed...,,, any progress Hans?




 

Thank you Hans!. I will E-mail you for the hex file.

Glenn


 

Hi Glenn,
I wonder if you have tried this beta file yet.
I had a few strange issues but mainly because with setting the AUX number on the WSPR mode screens and wondered if you had the same?

73 Ken G4apb?


 

Hi Ken,

No I haven't tried it yet mainly because my old programmer doesn't support the. Micro.
I may have to order a programmed chip.


 

I'd like to order two more U3S's but I need to have the firmware that works with potentiometer tuning. Unfortunately my programmer doesn't support the micro used in the U3S.

Will the potentiometer tuning option be available for current U3S orders?. I'm using the U3S as the basis for a self contained QRP transmitter and?potentiometer tuning is an absolute must have!

Glenn W2BX