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QCX LPF adjustments


ian liston-smith
 

Quick question:

Can the display module be removed so the LPF coils can be poked and tweaked for adjustment? Does removing the display module and powering up cause any problems? Will the rig still work so adjustments can be made?

If so it will make spacing/squashing the toroid turns with a cocktail stick for maximum power much easier.

Thanks.

Ian


Hans Summers
 

Hi Ian

Yes, you can remove the LCD and power-up, once you are confident everything is working fine. I do this all the time, for making adjustments to the LPF toroid spacing. QCX works fine without the LCD; it only talks at the LCD, it does not check for any answer back. So if the LCD is not present, the firmware doesn't notice or care. 

73 Hans G0UPL


On Wed, Apr 29, 2020 at 11:34 PM ian liston-smith <ian.ls@...> wrote:
Quick question:

Can the display module be removed so the LPF coils can be poked and tweaked for adjustment? Does removing the display module and powering up cause any problems? Will the rig still work so adjustments can be made?

If so it will make spacing/squashing the toroid turns with a cocktail stick for maximum power much easier.

Thanks.

Ian


Skip Davis
 

Yes Ian you can remove the display and make adjustments to the LPF windings. This will not hurt the QCX functionality and when you re-plug in the display all should be good again.

Skip Davis, NC9O


Hans Summers
 

One point to note...

If you plug an LCD into an already powered up QCX, then your LCD will show the dreaded row of black blocks. This is not a fault. This is just because the LCD requires a certain initialization sequence, which is executed by QCX at power-up. So if you plug in an LCD module afterwards, it hasn't had the initialization sequence and it just does nothing. So remember, when re-connecting the LCD module, you need to power-cycle the QCX. 

73 Hans G0UPL
http://qrp-labs.com

On Thu, Apr 30, 2020 at 12:23 AM Skip Davis via groups.io <skipnc9o=yahoo.com@groups.io> wrote:
Yes Ian you can remove the display and make adjustments to the LPF windings. This will not hurt the QCX functionality and when you re-plug in the display all should be good again.

Skip Davis, NC9O




Syd
 

As I understand this, pull out the LCD and then power it up. So no menu, and it will operate in default mode/frequency? Sending and receiving? In the QCX units there is a straight key, so I guess that it is used to get power out, and measure the power through the dummy load power pins to do the adjustment? But in the QCX+ version there is no key and the LCD is part of a PCB. So set it up for a straight key, unplug the LCD module, power up and use a straight key to get power output? Maybe it is feasible to do this procedure with the QCX+ version? I will probably have to work around the power button.
73 wt1v

On Wednesday, April 29, 2020, 4:52:15 PM EDT, Hans Summers <hans.summers@...> wrote:


Hi Ian

Yes, you can remove the LCD and power-up, once you are confident everything is working fine. I do this all the time, for making adjustments to the LPF toroid spacing. QCX works fine without the LCD; it only talks at the LCD, it does not check for any answer back. So if the LCD is not present, the firmware doesn't notice or care. 

73 Hans G0UPL


On Wed, Apr 29, 2020 at 11:34 PM ian liston-smith <ian.ls@...> wrote:
Quick question:

Can the display module be removed so the LPF coils can be poked and tweaked for adjustment? Does removing the display module and powering up cause any problems? Will the rig still work so adjustments can be made?

If so it will make spacing/squashing the toroid turns with a cocktail stick for maximum power much easier.

Thanks.

Ian


Hans Summers
 

Hi Syd
 
As I understand this, pull out the LCD and then power it up. So no menu, and it will operate in default mode/frequency? Sending and receiving? In the QCX units there is a straight key, so I guess that it is used to get power out, and measure the power through the dummy load power pins to do the adjustment? But in the QCX+ version there is no key and the LCD is part of a PCB. So set it up for a straight key, unplug the LCD module, power up and use a straight key to get power output? Maybe it is feasible to do this procedure with the QCX+ version? I will probably have to work around the power button.

When there is no LCD connected, the QCX/QCX+/QCX-mini doesn't care. It just operates as though the LCD is there. It powers up and provided it is not the first time (when you must choose the band of operation), it will operate at the default VFO frequency etc which you have set up. Then you can tweak LPFs etc. 

But I do not understand why you would need to do this on the QCX+ where the LCD is on a separate, perpendicular board, and does not impede access to the LPF toroids? 

73 Hans G0UPL
http://qrp-labs.com


Syd
 

I have a QCX and a QCX+ and got a little confused, I meant to be talking about the QCX!

Excellent UTube video on aligning!!!!

wt1v