¿ªÔÆÌåÓý

ctrl + shift + ? for shortcuts
© 2025 Groups.io
  1. QRPLabs
  2. Topics

QCX 5W TRX kit

 

If I blow Q6, could I use a ZTX551 transistor?? I have a bunch of them and have no 550s.? I think a ZTX551 is good for the same current as a 550 but can handle higher voltage then a 550.
Lee, w0vt

I blew Q6 as well :-( I replaced mine with a (pin compatible) ZTX550
which has a slightly higher rating (1A).
 

It is not likely that you'll break the MPS2907 but if you do, ZTX551 should be Ok too.

For the next batch I found the MPS751 which has easier availability, better price, and 2A capability. So we'll use MPS751.

73 Hans G0UPL?
?


On Sep 7, 2017 6:46 AM, "Leland L. Bahr" <l@...> wrote:
If I blow Q6, could I use a ZTX551 transistor?? I have a bunch of them and have no 550s.? I think a ZTX551 is good for the same current as a 550 but can handle higher voltage then a 550.
Lee, w0vt
I blew Q6 as well :-(? ?I replaced mine with a (pin compatible) ZTX550
which has a slightly higher rating (1A).
 

My three kits for 40, 30 and 20 meters got shipped today.? I've decided what configuration cabinet I want for my radios, but I have decided to concentrate on getting the radios built and working properly before concentrating on cabinets and power supplies.? This other stuff can wait.? I may anticipate where external parts may wind up while building the kits and accommodate them, but I am now sure one would do himself a favor by not getting to far ahead of the game.? Build the kit, get it working properly and then move on to cases and power supply types with rechargeable batteries and chargers.? I'm thinking there is going to be some tweaking needed before tackling these other concerns. That will be a big enough hurdle to overcome before taking on more challenges.? In other words, tackle this project one step at a time.? Keep it simple.

One other thing, I'd be curious in knowing who in the US and Canada are going to build an 80 meter version of the QCX.? (My 80 meter serial number is in the high 700s.)? Let me know.
Lee, w0vt
Lee@...
 

Lee W0VT wrote...

I'd be curious in knowing who in the US and Canada
are going to build an 80 meter version of the QCX.
(My 80 meter serial number is in the high 700s.)
I ordered one for 80M, #625, and then another for
40M the other day, but I don't have the serial number
for that one yet. I might be the the wrong side of
the continent for 80M, but we could give it a try.

I've been listening off and on with WSPR-X the last
day or two on 30M & 40M with no interface - just the
mic in a laptop picking up the audio from the speaker
in my "big" rig and it is quite amazing what it
decodes with people in the room talking, the parrot
squawking (pet sitting) and music playing (the parrot
likes opera) and voice QSOs over on another radio. I
ordered the QCXs for fun and to force me to try and
make a few CW contacts, but I can see that when I'm
not using it for anything else, it is probably
going to be in WSPR mode.

--
73 Keith VE7GDH
 

¿ªÔÆÌåÓý

I ordered an 80m, 40m, 30m, and 20m kit. The 80m and 40m were first , 30M second, and 20M was today

73
NE5U

Mike

September 7, 2017 at 10:43 PM
Lee W0VT wrote...

> I'd be curious in knowing who in the US and Canada
> are going to build an 80 meter version of the QCX.
> (My 80 meter serial number is in the high 700s.)

I ordered one for 80M, #625, and then another for
40M the other day, but I don't have the serial number
for that one yet. I might be the the wrong side of
the continent for 80M, but we could give it a try.

I've been listening off and on with WSPR-X the last
day or two on 30M & 40M with no interface - just the
mic in a laptop picking up the audio from the speaker
in my "big" rig and it is quite amazing what it
decodes with people in the room talking, the parrot
squawking (pet sitting) and music playing (the parrot
likes opera) and voice QSOs over on another radio. I
ordered the QCXs for fun and to force me to try and
make a few CW contacts, but I can see that when I'm
not using it for anything else, it is probably
going to be in WSPR mode.

September 7, 2017 at 9:18 PM
My three kits for 40, 30 and 20 meters got shipped today.? I've decided what configuration cabinet I want for my radios, but I have decided to concentrate on getting the radios built and working properly before concentrating on cabinets and power supplies.? This other stuff can wait.? I may anticipate where external parts may wind up while building the kits and accommodate them, but I am now sure one would do himself a favor by not getting to far ahead of the game.? Build the kit, get it working properly and then move on to cases and power supply types with rechargeable batteries and chargers.? I'm thinking there is going to be some tweaking needed before tackling these other concerns. That will be a big enough hurdle to overcome before taking on more challenges.? In other words, tackle this project one step at a time.? Keep it simple.

One other thing, I'd be curious in knowing who in the US and Canada are going to build an 80 meter version of the QCX.? (My 80 meter serial number is in the high 700s.)? Let me know.
Lee, w0vt
Lee@...





 

Lee & Keith,

FYI - I ordered a 20m QCX #407 ...thinking of building it up for my SOTA adventures! Probably put it in a waterproof case as is just using a plastic cover plate to ID controls and keep electronics safe ...maybe with audio amp (no headphones as I need to hear what the goats are up too), with EFHW xformer and room for battery and ant/wire ...oh and a touch paddle with acorn nuts on exterior ...sort of a one box solution to toss in my pack! ?

May order another (maybe several?) if get #407 up and running and love/like it ...QSK, YAH!! & 5W!! - plus the amazing laundry list of features made me jump on this value kit! Haven't looked recently where the order/shipment #s are but I'm in no hurry I've many projects keeping me in and out of trouble! ?

73, Steve/wGOAT
 

¿ªÔÆÌåÓý

Steve was that you I QSO just now on 20m with the suspicious callsign of YJ0AT knowing you float all around the Pacific you never cease to amaze me where you pop up, or was that someone else who knows my name and infamous callsign?!

Note that you will only get 5W out on 15V see the charts at the bottom of

So you SOTA AND IOTA adventurer are you ever on simple flat dry land? Presumably not, water proof case, mind you with the increasing floods and chaos a good idea for us all?

Would you recommend I get a box sized 140x110x35mm Oval ABS Plastic Case I can get 5 of those for 99c each, or 205 x 157 x 63mm ABS Medium Enclosure I can get one of those for $8. I guess the bigger box can hide more things in it, batteries, MEF-1 EFHW match, loudspeaker, audio amplifier, and perhaps a baby goat too!?

73 es 77 de Lou VK5EEE
On 8/09/2017 1:52 PM, goathiker@... wrote:

Lee & Keith,

FYI - I ordered a 20m QCX #407 ...thinking of building it up for my SOTA adventures! Probably put it in a waterproof case as is just using a plastic cover plate to ID controls and keep electronics safe ...maybe with audio amp (no headphones as I need to hear what the goats are up too), with EFHW xformer and room for battery and ant/wire ...oh and a touch paddle with acorn nuts on exterior ...sort of a one box solution to toss in my pack! ?

May order another (maybe several?) if get #407 up and running and love/like it ...QSK, YAH!! & 5W!! - plus the amazing laundry list of features made me jump on this value kit! Haven't looked recently where the order/shipment #s are but I'm in no hurry I've many projects keeping me in and out of trouble! ?

73, Steve/wGOAT

 

Good to hear from you Keith.? I only got two responses of guys buying 80 meter versions.? I guess 80 is just not very popular these days.? Anyway, I have an offer if you want it.? The T1 transformer is not big enough to wind this transformer without overlapping turns.? Hans is supplying a wire too large.? I have some #30 magnet wire that will allow you to wind all 4 windings on T1 and not have to overlap turns.? I can send you 10 foot of it free of charge if you want to use #30.? Let me know and if so, are you good on QRZ?

Lee, w0vt

On 9/7/2017 10:43 PM, Keith VE7GDH wrote:
Lee W0VT wrote...

I'd be curious in knowing who in the US and Canada
are going to build an 80 meter version of the QCX.
(My 80 meter serial number is in the high 700s.)
I ordered one for 80M, #625, and then another for
40M the other day, but I don't have the serial number
for that one yet. I might be the the wrong side of
the continent for 80M, but we could give it a try.

I've been listening off and on with WSPR-X the last
day or two on 30M & 40M with no interface - just the
mic in a laptop picking up the audio from the speaker
in my "big" rig and it is quite amazing what it
decodes with people in the room talking, the parrot
squawking (pet sitting) and music playing (the parrot
likes opera) and voice QSOs over on another radio. I
ordered the QCXs for fun and to force me to try and
make a few CW contacts, but I can see that when I'm
not using it for anything else, it is probably
going to be in WSPR mode.
 

Lee W0VT wrote...

I have some #30 magnet wire that will allow you
to wind all 4 windings on T1 and not have to
overlap turns. I can send you 10 foot of it free
of charge if you want to use #30.
Thanks for the offer, but hold off. I have small
small gauge wire here. I'm not sure if it's #30,
but it must be pretty close.

However, doesn't it say in the assembly instructions
that it is "OK" to have overlaps in the 68 turns in
the 80M version? I agree that it would look neater
without the overlaps though!

--
73 Keith VE7GDH

1 - 9 of 9