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QMX on high bands?

 

Possibly an incredibly stupid question, but I can't find the answer. ;-)

Can the "high bands" kit (i.e. the one with different capacitors and toroids) for the QDX be used in the QMX?

And is there a set of instructions anywhere for converting a "low bands" QDX (that I have, and works well) into the "high bands" version?

Best 73 Mark G?OIW
 

Hello Mark

The high bands kit is for the QDX. Not QMX. It can't be used in the QMX because the QMX uses smaller toroids to fit in the smaller available space. I will have a solution available in due course.?

73 Hans G0UPL



On Tue, Jul 18, 2023 at 12:56?PM Mark Palmer <esperanto2023@...> wrote:
Possibly an incredibly stupid question, but I can't find the answer. ;-)

Can the "high bands" kit (i.e. the one with different capacitors and toroids) for the QDX be used in the QMX?

And is there a set of instructions anywhere for converting a "low bands" QDX (that I have, and works well) into the "high bands" version?

Best 73 Mark G?OIW
 

Many thanks!
 

I'm looking forward to the 'high band' option, given where we are in the solar cycle. Having said that, developing a 'mid-band' option would be nice, in 'the fullness of time', as Sir Humphrey would say...

73 de va3rr

On Tue, Jul 18, 2023 at 05:58 AM, Hans Summers wrote:

I will have a solution available in due course.
 

RR,
?I vote for a 40-15 version as well. But I would take a high band one, too. Right now I'll be very happy to see the next firmware version!
--
73, Dan? NM3A
 

I'd also like to see a "mid-band" option - 40/30/20/17/15.

73,
Mike, KL7MJ
 

Hey Mike - that would be an amazing set of bands when I'm out portable.? Nice balance between antenna size and usable bands both locally and DX when hiking.

73/72
Jeff - VE3CW / VA3JFF
 

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This mid range option looks achievable with the existing kit, something like this :-

Start by not installing the 80m LPF parts, build and test on 60/40/30/20.

Add a tap to the BPF inductor at 13 or 14 turns,? set up Rx on 17 and 15 using that.? Doing this might also change the other bands so check them.

Then build and install a LPF in the 80m location tuned for 17/15 using the values from the QDX kit.? This might need new T30-17 toroids and the correct capacitors. It might be possible to use the 80m T30-6 toroid with different winding.

I've almost certainly grossly underestimated how difficult this is but at least these are incremental changes so it shouldn't be too difficult to retreat.? May try this when mine arrives.

Chris, G5CTH
 

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Hi all,

I’m currently working on getting the HB LPFs right and doing the first prototype QMX HB. It will be a little while though not too long as the QDX HB LPFs are fine, just need to get the values on T30-17s and T30-0s so no saturation.?
When released perplexed will be able to run their own combos of LPFs as they choose. BPFs won’t be that difficult to do either.?
It’s easy to run combos of
10/11/12
15/17
17/20 and even
20/17/15?
In LPFs.

BPFs are easy enough but remember only 4 switchable locations in the hardware, with a bit of compromise some multiple combos are possible.?

We will do straight 20/17/15/12/11/10 first up.?
73

Ross

6

On 20 Jul 2023, at 01:08, Jeff <jeff.ve3cw@...> wrote:

?Hey Mike - that would be an amazing set of bands when I'm out portable.? Nice balance between antenna size and usable bands both locally and DX when hiking.

73/72
Jeff - VE3CW / VA3JFF

 

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Perplexed=people.?

6

On 20 Jul 2023, at 14:12, Afghan Kabulldust via groups.io <kabulldust@...> wrote:

?Hi all,

I’m currently working on getting the HB LPFs right and doing the first prototype QMX HB. It will be a little while though not too long as the QDX HB LPFs are fine, just need to get the values on T30-17s and T30-0s so no saturation.?
When released perplexed will be able to run their own combos of LPFs as they choose. BPFs won’t be that difficult to do either.?
It’s easy to run combos of
10/11/12
15/17
17/20 and even
20/17/15?
In LPFs.

BPFs are easy enough but remember only 4 switchable locations in the hardware, with a bit of compromise some multiple combos are possible.?

We will do straight 20/17/15/12/11/10 first up.?
73

Ross

6

On 20 Jul 2023, at 01:08, Jeff <jeff.ve3cw@...> wrote:

?Hey Mike - that would be an amazing set of bands when I'm out portable.? Nice balance between antenna size and usable bands both locally and DX when hiking.

73/72
Jeff - VE3CW / VA3JFF

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