Date   

Re: Will this balun work ok? #40m #antenna

Kevin Zembower
 

Can you tell me what the name of those boxes is? What can I search for? What are the approximate dimensions?

Thanks so much.

-Kevin
KC3KZ


Adjusting 20m QSX - No output on pin 7 of IC5

Christian <Ch.fiedler@...>
 

Hallo,

I got my QSX kit a couple of weeks ago. Yesterday I built up the 20m version.

The digital part seems to be ok. The display and all the switches work well. But I have some
troubles adjusting the rx path.

I could find a peak under 8.7 Peak BPF, but the level is too low - reading about 5 in the level meter.
So I bypassed the R43 120k with 10k. And followed the troubleshooting page. I could follow the signal
until IC5. The I path is ok - I got a nice sine wave at Pin 1 of IC5 - but the Q path is not ok. At pin 7
of IC5 the output is fix at 12.5V. On pin 5 I could see the input sine wave.
I checked everything around IC - everything looks fine. So I cut out the IC and soldered a socket and
put a new IC5 in. But I got the same result.
Measuring the static values I found a low resistance of 17ohms between R9/C45 and ground.
So I removed the R9 and C45 and again I measure only 17ohms between the output pins 12/5 of IC4 and
ground. Again I checked the connections between IC 5 and IC 4 - but everything looks ok.

Is IC4 blown up? If I is, what is the best way to replace the SMD IC?

Many thanks for the help in advance.

Christian


Re: Will this balun work ok? #40m #antenna

ajparent1/KB1GMX
 

JohnL,

Short answer is no.

Longer answer is see AA5TB site http://www.aa5tb.com/index.html look at anything EFHWin the  index.

For a monoband radio a simple tuned coupler with a ~1:9 turns ratio should do the job well.


Allison


Re: Will this balun work ok? #40m #antenna

Andy Brilleaux <punkbiscuit@...>
 

On Fri, Aug 2, 2019 at 10:39 AM, Cor Beijersbergen wrote:
He did not mention QRP
But it was posted to the QRP-labs group, not the QRO-Labs group ;-)

Joking aside, those little ferrite rings will do 5w with ease, and I've run them for hours in beacon mode with 15-20w
and no warming / losses.

Output stage was running into a dummy load for the test.

73 de Andy


Re: QCX 40 Headphone Noise #qcx

mx201er@...
 

Thanks Steve! I've already had a couple closer individuals offer to help me out; I appreciate all of the knowledgeable and friendly people in this hobby.

Thanks all,
Nick


Re: QCX 20m Transciever - Cannot Make IQ balance adjustments #alignment

Nick
 

Thank you to all that sent me information.  I will try your various suggestions this evening and then post the thread on what I have found.
What a great community!  Thanks so much for all your help!
--
73! de Nick K9XN


Re: Will this balun work ok? #40m #antenna

Russ@va3rr
 

A 140 toroid fits nicely in those inexpensive boxes commonly found on auction sites,,,


Re: Will this balun work ok? #40m #antenna

Cor Beijersbergen
 

A 140 would certainly be an overkill for QRP, but John did not mention the power of his rig. He did not mention QRP. A 140 would make a 100 Watts possible, I use that myself.

 

Cor – PA4Q

 

From: QRPLabs@groups.io <QRPLabs@groups.io> On Behalf Of Karlis Goba
Sent: Friday, 2 August 2019 10:02
To: QRPLabs@groups.io
Subject: Re: [QRPLabs] Will this balun work ok? #40m #antenna

 

Cor, I agree with your detailed analysis. However, isn't a 140 size toroid an overkill for QRP levels?

--
Karlis YL3JG


Re: Will this balun work ok? #40m #antenna

Kārlis Goba
 

Cor, I agree with your detailed analysis. However, isn't a 140 size toroid an overkill for QRP levels?

--
Karlis YL3JG


Re: QCX Challenge

Andy
 

Hi Tony, Zdenek

OK for tomorrow(03.08.) 0335 utc on 7032 +/- qrm. Will find you on RBN :)

Also other US stations are welcome.

73

Andy 9a3jh

On 8/2/19 9:33 AM, Zdenek OK2BQN wrote:
Hi Tony,
I will also try to call you on frequency 7032 at 0335z-0345z 3 August.
I think I'll hear Andy.
73
Zdenek OK2BQN


Re: QCX Challenge

Zdenek OK2BQN
 

Hi Tony,
I will also try to call you on frequency 7032 at 0335z-0345z 3 August.
I think I'll hear Andy.
73
Zdenek OK2BQN


Re: Will this balun work ok? #40m #antenna

Cor Beijersbergen
 

Hello John,

 

Your balun looks exactly like the ones sold on ebay now for listening. These are 1:9 with a core of unknown properties.

You have to make a decision, you could make a resonant halfwave endfed or a random length non resonant endfed.

 

Halfwave resonant:

Your wire length is almost correct, but the balun needs to be 1:49. You need a SWR meter to prune the wire to length, after that you don’t need a tuner and you may work other bands as well (20, 15 and 10).

 

Random length endfed:

The wire length is wrong, because it is almost resonant on 40 and with a random length piece of wire and a 1:9 balun it should not be. And you will need a tuner.

By choosing the correct length of wire you could work more bands also.

 

General:

The toroid in the balun is very small and the material is of unknown properties. I recognise the balun, it is being sold on ebay now as a very cheap balun for listening only. I don’t know what kind of transmitter you intend to use, what the power level is an what internal protection of the power stage it has but I would not risk my transmitter on this balun.

But it lends itself for improvement, a new toroid with a 1:49 winding of the right size (a 140-43 will not fit in the housing) may give you a decent balun for a halfwave endfed.

Google for “halfwave endfed” or “EFHW” and you will find lots of information.

 

Succes!

Cor – PA4Q

 

 

 

From: QRPLabs@groups.io <QRPLabs@groups.io> On Behalf Of JohnL
Sent: Friday, 2 August 2019 02:39
To: QRPLabs@groups.io
Subject: [QRPLabs] Will this balun work ok? #40m #antenna

 

i have this balun from an old end fed 1/2 wave antenna that I was using for listening.  I cut a new 70ft chunk of speaker wire for transmitting on 40m.  I don’t have an antenna tuner and I am just getting started with my first radio.  Does this balun look okay to use and it won’t harm the radio?  I doesn’t quite look like other 1:9 end fed 1/2 wave baluns that I have been reading about.  Here are some picts. 

Thanks 
johnl


Re: QCX 40 Headphone Noise #qcx

Stephen Farthing G0XAR JO92ON97
 

Nick,

I’m in the EU so it won’t be practical to ship it to me. I’m sure there are plenty of helpers across the pond in your country. 

Regards, 

Steve 


Will this balun work ok? #40m #antenna

JohnL
 

i have this balun from an old end fed 1/2 wave antenna that I was using for listening.  I cut a new 70ft chunk of speaker wire for transmitting on 40m.  I don’t have an antenna tuner and I am just getting started with my first radio.  Does this balun look okay to use and it won’t harm the radio?  I doesn’t quite look like other 1:9 end fed 1/2 wave baluns that I have been reading about.  Here are some picts. 

Thanks 
johnl


Re: QCX 40 Headphone Noise #qcx

mx201er@...
 

I am located in the "four corners" area; Farmington, New Mexico.

-Nick KI5DAF


Re: 8,000 QCX kits...

jjpurdum
 

If anyone took my suggestion as being critical of anyone or any thing, that was not the case at all. I was simply trying to push the ball back into Hans' court so he can decide without us bugging him.

Jack, W8TEE

On Thursday, August 1, 2019, 4:21:46 PM EDT, Bill Cromwell <wrcromwell@...> wrote:


Obviously number 10,000 is some time into the distant future. Further it
so obviously up to Hans. It is not our radio to sell (yet). I think the
whol idea of this thread is to gage trhe interest in these radios.

It's all in fun. If anybody here doesn't like fun maybe ham radio is not
for you.

And now this particular nobody will just shut up.


On 8/1/19 4:07 PM, jjpurdum via Groups.Io wrote:
> I kinda agree. We're going to use up bandwidth for sometime, and that
> time length is unknown right now. If Hans wants to do this, perhaps the
> best way to proceed is to have Hans announce: 1) he does want to sell
> unit 10,000, and 2) he wants to hold it back for auction. Given that,
> Hans could post a notice here saying: "Serial number 10000 has been
> produced and I am offering it for auction. You have XX days to place a
> bid using this email address XXXXXX@.... I will announce the
> winner at (XX+5) days from now."
>
> If he wants to set up a private email account now, fine, as that would
> avoid postings that are of little interest to those who are not
> interested in the unit.
>
> Jack, W8TEE

--
bark less - wag more




Re: 8,000 QCX kits...CHINA

Steve in Okinawa
 

 There are more Chinese stations in the air every day on the HF bands, and CW seems to be very popular. Granted, many are using keyboards/decoders and don't stick around for a nice ragchew, but at least they are having a go. And I hear a /QRP now and then as well. I haven't heard about any SOTA there, but it's catching on in Taiwan and Hong Kong.  73 from Okinawa JS6TMW 


Re: 8,000 QCX kits...

Glen Sr
 

I apologize to this group of wonderful people for my silly bid! And I mean it!! Regards. Glen N8WE

-----Original Message-----
From: Bill Cromwell
Sent: Thursday, August 1, 2019 4:21 PM
To: QRPLabs@groups.io
Subject: Re: [QRPLabs] 8,000 QCX kits...

Obviously number 10,000 is some time into the distant future. Further it
so obviously up to Hans. It is not our radio to sell (yet). I think the
whol idea of this thread is to gage trhe interest in these radios.

It's all in fun. If anybody here doesn't like fun maybe ham radio is not
for you.

And now this particular nobody will just shut up.


On 8/1/19 4:07 PM, jjpurdum via Groups.Io wrote:
I kinda agree. We're going to use up bandwidth for sometime, and that time length is unknown right now. If Hans wants to do this, perhaps the best way to proceed is to have Hans announce: 1) he does want to sell unit 10,000, and 2) he wants to hold it back for auction. Given that, Hans could post a notice here saying: "Serial number 10000 has been produced and I am offering it for auction. You have XX days to place a bid using this email address XXXXXX@.... I will announce the winner at (XX+5) days from now."

If he wants to set up a private email account now, fine, as that would avoid postings that are of little interest to those who are not interested in the unit.

Jack, W8TEE
--
bark less - wag more


Re: T1 wire gauge

Greg Walters
 

Haha! I may need new glasses (I have bifocals, plus used a big magnifying glass), but this was my 3rd 40 meter QCX. All 3 have 38-39 windings on the 3rd secondary. They all align quite nicely. 

I really enjoy building these kits. I'm excited to get my hands on the QSX once Hans gets it completed. I know he'll have 99% of the bugs worked out before he releases it. That's why his kits are so good. 
--
73,
Greg
KY4GW


Re: QCX 40 Headphone Noise #qcx

Stephen Farthing G0XAR JO92ON97
 

Nick, 
Where are you located?
Steve G0XAR