QCX vs. QCX+ Form Factor Question


Damon Carpenter - K5RZ
 

First, let me say for certain that I'm very excited by the new QCX+. Hans, you did a great job building out more room and convenience in this great little transceiver.

But I wonder whether this new desktop version runs against one of the key features that made the QCX popular in the first place - the compact form factor.  True, the original QCX had some quirks that made enclosures challenging. But a "cottage industry" had grown up around how to solve those challenges and make the QCX fit into a tiny box for backpacking, hiking, biking, etc. The new version seems to create more challenges for that deployment mode than the original. Being relatively new to the QRP kit-building world, I wonder if anyone on the group here has ideas on how to make the new QCX+ more compact than the form factor of the new enclosure.

73,
K5RZ


Hans Summers
 

Hi Damon

You could get a box slightly larger than the 10 x 13cm PCB, and mount the display and buttons board in the top of it. 

Over time there have been people who asked for QCX to be bigger (lower component density). I've done that. The new QCX+ will be easier to make for many people, and will be easier to modify and experiment with. But it is as small, this is true. Overall it's hard to please everyone in one product!

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

On Mon, May 25, 2020 at 11:10 PM <damon.carpenter@...> wrote:
First, let me say for certain that I'm very excited by the new QCX+. Hans, you did a great job building out more room and convenience in this great little transceiver.

But I wonder whether this new desktop version runs against one of the key features that made the QCX popular in the first place - the compact form factor.  True, the original QCX had some quirks that made enclosures challenging. But a "cottage industry" had grown up around how to solve those challenges and make the QCX fit into a tiny box for backpacking, hiking, biking, etc. The new version seems to create more challenges for that deployment mode than the original. Being relatively new to the QRP kit-building world, I wonder if anyone on the group here has ideas on how to make the new QCX+ more compact than the form factor of the new enclosure.

73,
K5RZ


Shirley Dulcey KE1L
 

One approach would be to use the extra space for a battery, making one less item you need to carry. Or how about an internal ATU?


On Mon, May 25, 2020 at 4:18 PM Hans Summers <hans.summers@...> wrote:
Hi Damon

You could get a box slightly larger than the 10 x 13cm PCB, and mount the display and buttons board in the top of it. 

Over time there have been people who asked for QCX to be bigger (lower component density). I've done that. The new QCX+ will be easier to make for many people, and will be easier to modify and experiment with. But it is as small, this is true. Overall it's hard to please everyone in one product!

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

On Mon, May 25, 2020 at 11:10 PM <damon.carpenter@...> wrote:
First, let me say for certain that I'm very excited by the new QCX+. Hans, you did a great job building out more room and convenience in this great little transceiver.

But I wonder whether this new desktop version runs against one of the key features that made the QCX popular in the first place - the compact form factor.  True, the original QCX had some quirks that made enclosures challenging. But a "cottage industry" had grown up around how to solve those challenges and make the QCX fit into a tiny box for backpacking, hiking, biking, etc. The new version seems to create more challenges for that deployment mode than the original. Being relatively new to the QRP kit-building world, I wonder if anyone on the group here has ideas on how to make the new QCX+ more compact than the form factor of the new enclosure.

73,
K5RZ


Damon Carpenter - K5RZ
 

Thanks, Hans! I completely understand not being able to make everyone happy. 

Thanks for the suggestion of moving the face panel off the end of the main board. Looking at the pics of the boards, it looks like there are a few connections I'd need to make. Are those easily accomplished with a few ribbon cables? Or are there more complicated connections there?

Thanks again!

Damon C
K5RZ


Hans Summers
 

Hi Damon

Everything should be easy with a few ribbon cables. Nothing more... 

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

On Wed, May 27, 2020 at 9:26 PM <damon.carpenter@...> wrote:

Thanks, Hans! I completely understand not being able to make everyone happy. 

Thanks for the suggestion of moving the face panel off the end of the main board. Looking at the pics of the boards, it looks like there are a few connections I'd need to make. Are those easily accomplished with a few ribbon cables? Or are there more complicated connections there?

Thanks again!

Damon C
K5RZ


Scott - N1ST <n1st@...>
 

Hans,

Just to let you know that there are some out here whose radio will never leave the house, so bigger is better.  At least my mind.  :-)

Scott


Damon Carpenter - K5RZ
 

Great news, Hans. Thank you very much for confirming. 

May you sell 50,000 units in 2020 alone!

73,

Damon
K5RZ


Serge, ON4AA
 

Hi Hans,

I am also somewhat disappointed about the new form factor for backpacking use.

However, I really liked Shirley's suggestion of using the empty space for mounting —perhaps— three rechargeable 18650 Li-ion cells with charge controller and battery management.

Would it be possible, Hans, to measure up the dimensions of the empty space inside (in mm)? In other words, what is the largest rectangular box that would fit inside the empty space?

Thank you in advance for this information.

73 Serge, ON4AA


Serge, ON4AA
 

I am looking for a clearance of 92 × 70 × ~35 mm to fit those 3S 18650s with their BMS. Would that fit inside the empty space of the planned enclosure?


Hans Summers
 

Hi Serge

If you assume that the through hole components on the upper side of the PCB require 12mm of space - which is approximately true in the case of some tall components such as upright toroids and the electrolytic capacitors - then the available volume is 96mm wide x 30.5mm high x 120mm deep. 

I'm not sure why you would need 92 x 70 x 35mm for three 18650 cells. By definition the size of a 18650 is 18mm diameter and 65.0mm length (this is in the type name). Three of these would therefore fit in a space with dimensions 65 x 54 x 18mm. I know you said there is charge controller and battery management circuit... but unless these are very big, or I am missing something, this battery pack should easily fit, even twice! 

73 Hans G0UPL

On Fri, May 29, 2020 at 4:38 AM Serge, ON4AA <serge@...> wrote:

I am looking for a clearance of 92 × 70 × ~35 mm to fit those 3S 18650s with their BMS. Would that fit inside the empty space of the planned enclosure?


Serge, ON4AA
 

Here is the Wondom BCPB2 3S 18650 MPPT BMS I am talking about. Leaving out the DC connector, it is still 31.5 mm high with the electrolytic capacitors being the next highest components. However, if necessary, 1 mm can still be shaved off by replacing the 18650 cell holders.

It is pretty cheap, to the point that you perhaps could integrate it with your transceiver by default. The MPPT allows it to be used with a 18 to 24 V solar panel.

I got the idea of a video from Gil, F4WBY. He also employs this to supply power to his QCX radios. (Do not follow his suggestion of soldering directly to the cell terminals, though. Just apply once external power to the board to get it running.)

Wondom 3S 18650 BMS

The newer version PCBs have extra headers to drive external power level LEDs, without the need to add any extra series resistors.


Hans Summers
 

Hi Serge

Yes, I see...

The wide thickness of your assembly is due to the circuit board and the battery holders all adding up as thickness. 

Well there are some potential ways you could make it fit. The area is large. But 30.5mm is the limit to the depth - this assumes the components above the QCX+ PCB are allowed a height of 12mm. The only components which need this height are the LPF toroids, the electrolytic capacitors, and the 24-turn trimmer potentiometers. 

So perhaps, with careful orientation, your board could be positioned such that the "high" parts of the QCX+ circuit didn't interfere with the big parts of the battery controller board. Bolt the board to the roof with standoffs and make sure the positioning is such that the stalagmites never meet the stalagmites. 

OR... use the QCX+ Dev kit board, and separate the battery holders of your assembly, from the board. There seems to be plenty of space to have them side by side. 

OR... you could make the LPF toroids in the QCX+, and the capacitors and 24-turn trimmer pots, lie down - where necessary? The QCX+ PCB has lots of spare area so there is room to make things like down like that. 

Several options - but will take some experiment! 

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

On Fri, May 29, 2020 at 1:11 PM Serge, ON4AA <serge@...> wrote:

Here is the Wondom BCPB2 3S 18650 MPPT BMS I am talking about. Leaving out the DC connector, it is still 31.5 mm high with the electrolytic capacitors being the next highest components. However, if necessary, 1 mm can still be shaved off by replacing the 18650 cell holders.

It is pretty cheap, to the point that you perhaps could integrate it with your transceiver by default. The MPPT allows it to be used with a 18 to 24 V solar panel.

I got the idea of a video from Gil, F4WBY. He also employs this to supply power to his QCX radios. (Do not follow his suggestion of soldering directly to the cell terminals, though. Just apply once external power to the board to get it running.)

Wondom 3S 18650 BMS

The newer version PCBs have extra headers to drive external power level LEDs, without the need to add any extra series resistors.


Serge, ON4AA
 

Yes, Hans, I also see potential for your stalagmites not meeting my stalactites :-D

On a different note, will the enclosure have a pair of folding feet under the front? I want to avoid getting a stiff neck in the field… (not the US police kind of stiff neck, though.)


Hans Summers
 

Hi Serge

There are no folding feet. If someone has a suggestion, that could become popular. As supplied, it will, as documented, have four self-adhesive feet. 

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

On Fri, May 29, 2020 at 4:20 PM Serge, ON4AA <serge@...> wrote:

Yes, Hans, I also see potential for your stalagmites not meeting my stalactites :-D

On a different note, will the enclosure have a pair of folding feet under the front? I want to avoid getting a stiff neck in the field… (not the US police kind of stiff neck, though.)


Roger Hill
 

I would prefer a wire bail that folds down, rather than folding feet. I find that folding feet (e.g. like on the Drake R8) tend to be flimsy.

Roger

G3YTN

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Roger Hill
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On 2020-05-29 09:51, Hans Summers wrote:

Hi Serge
 
There are no folding feet. If someone has a suggestion, that could become popular. As supplied, it will, as documented, have four self-adhesive feet. 
 
73 Hans G0UPL
http://qrp-labs.com

On Fri, May 29, 2020 at 4:20 PM Serge, ON4AA <serge@...> wrote:

Yes, Hans, I also see potential for your stalagmites not meeting my stalactites :-D

On a different note, will the enclosure have a pair of folding feet under the front? I want to avoid getting a stiff neck in the field... (not the US police kind of stiff neck, though.)




Ted 2E0THH
 

Hi Serge
I use these folding feet on my rig which employs very similar boxes to the one destined for the QCX+







https://www.metcase.co.uk/en/Enclosure-Feet/M6420204.htm

Roger
I have successfully made a bale for the stepper driver box that drives my telescope. I used a coat hanger, one I found with very think wire. Just used a vice, a hammer, some trig and an awful lot of Anglo Saxon. Very pleased with the result.

73s Ted
2E0THH