Re: Photos of a 30m beacon build, and a question about the oscillator frequency

Dave Clausen

Success! I'm QRV now and visible on ON5EX's grabber. It looks like I'm
centered at about 10.140.0010 MHz, slowly drifting down, with a shift
of 4 or 5 Hz. That is about what I estimated at home using a
general-purpose audio spectrometer program on my Mac.

This is cool. Are there any other working grabbers online I can check?
 So far ON5EX's is the only one I've found that is actively updating.

72/73, Dave W2VV

Re: Photos of a 30m beacon build, and a question about the oscillator frequency

"hanssummers2000"

#112

Hi Dave

This week I finally put together the 30m QRSS beacon kit I bought from
G0UPL at FDIM.  I added a 5v linear regulator to allow operation from
a 9V battery, and an LED to show keying activity, and put the whole
thing in an Altoids tin.  I uploaded some photos here:

Wow Dave. Fine photos! Most of my photos are taken with the camera in my Nokia E90 mobile phone. Your camera is doing a much nicer job!


One issue that came up is that I had a hard time getting my oscillator
frequency down to 10.140.050 MHz.  Initially I couldn't get it below
10.140.220.  I removed and re-wound L1 with 38 turns but that only
lowered me to about 10.140.100.  So I added a 10pF capacitor across C9
and that brought my min frequency down below 10.140.000 (easily raised
by tuning C9).  Although it seems to work fine now, I'm wondering if I
might have created a problem that I'm not aware of, or if the initial
high frequency was an indication of a mistake I made during the build.
Any thoughts?I haven't heard of this problem before. Perhaps you just had a crystal that was some way off the normal frequency. I shouldn't think you made any mistake building, or that the remedial action you took would cause any other problem.

Your "gimmick" capacitor looks long... I wonder if it will create a wide FSK much more than 5Hz. Did you measure your amount of FSK?


I hope to put the beacon on the air on Friday night from my club in
Brooklyn, NY. This is my first attempt at QRSS and I'm really excited
to look for my signal on the grabbers tomorrow. Thanks Hans for a
great kit.Good luck! Let us know how it goes.

73 Hans G0UPL

Photos of a 30m beacon build, and a question about the oscillator frequency

Dave Clausen

#111

Hi All-

This week I finally put together the 30m QRSS beacon kit I bought from
G0UPL at FDIM.  I added a 5v linear regulator to allow operation from
a 9V battery, and an LED to show keying activity, and put the whole
thing in an Altoids tin.  I uploaded some photos here:



One issue that came up is that I had a hard time getting my oscillator
frequency down to 10.140.050 MHz.  Initially I couldn't get it below
10.140.220.  I removed and re-wound L1 with 38 turns but that only
lowered me to about 10.140.100.  So I added a 10pF capacitor across C9
and that brought my min frequency down below 10.140.000 (easily raised
by tuning C9).  Although it seems to work fine now, I'm wondering if I
might have created a problem that I'm not aware of, or if the initial
high frequency was an indication of a mistake I made during the build.
Any thoughts?

I hope to put the beacon on the air on Friday night from my club in
Brooklyn, NY. This is my first attempt at QRSS and I'm really excited
to look for my signal on the grabbers tomorrow. Thanks Hans for a
great kit.

72/73, Dave W2VV

At ham radio 2010

Jim Stafford

#110

Wb4mak es I are at ham radio 2010 in friedrichaffen.  Will look for u all.
W4QO Jim Stafford www.w4qo.com QRP - When you care enough to send the very least!

Show quoted text

--- On Wed, 6/23/10, Mike <mikeberg@...> wrote:

From: Mike <mikeberg@...>
Subject: [QRPLabs] Re: Hans Summer's web page 30m transmitter
To: QRPLabs@...
Date: Wednesday, June 23, 2010, 11:06 AM

?

Thanks Hans,

I figured I might experiment with that design until
you're able to start shipping kits.

73 Mike  N0QBH

--- In QRPLabs@...,
"hanssummers2000" <hans.summers@...> wrote:

Hi MikeCan anyone tell me the values of the voltagedivider resistors biasing LED varicap in the schematic on
this page? 

I think the upper resistor is 33k but have noclue what the grounded one is.

Even I can't tell you that, sorry :-(   Looks likeI shrunk that diagram too much. The good news is that the
values are entirely non critical. You could try with 33k in
both positions to start with. I believe I chose the values
in haste. It was merely to achieve, together with the 100K
resistor to the 4-bit digital-to-analogue converter, the
right amount of shift that I wanted. No magic to it. I think
it's just a matter of playing with the values until you
get the shift amount you want, subject to the component
tolerances and LED characteristics you have in your
circuit.

73 Hans G0UPL

Re: Hans Summer's web page 30m transmitter

"Mike"

#109

Thanks Hans,
I figured I might experiment with that design until you're able to start shipping kits.

73 Mike  N0QBH

Show quoted text

--- In [email protected], "hanssummers2000" <hans.summers@...> wrote:

Hi Mike

Can anyone tell me the values of the voltage divider resistors biasing LED varicap in the schematic on this page? 

I think the upper resistor is 33k but have no clue what the grounded one is.Even I can't tell you that, sorry :-(   Looks like I shrunk that diagram too much. The good news is that the values are entirely non critical. You could try with 33k in both positions to start with. I believe I chose the values in haste. It was merely to achieve, together with the 100K resistor to the 4-bit digital-to-analogue converter, the right amount of shift that I wanted. No magic to it. I think it's just a matter of playing with the values until you get the shift amount you want, subject to the component tolerances and LED characteristics you have in your circuit.

73 Hans G0UPL

Re: Hans Summer's web page 30m transmitter

"hanssummers2000"

#108

Hi Mike

Can anyone tell me the values of the voltage divider resistors biasing LED varicap in the schematic on this page? 

I think the upper resistor is 33k but have no clue what the grounded one is.Even I can't tell you that, sorry :-(   Looks like I shrunk that diagram too much. The good news is that the values are entirely non critical. You could try with 33k in both positions to start with. I believe I chose the values in haste. It was merely to achieve, together with the 100K resistor to the 4-bit digital-to-analogue converter, the right amount of shift that I wanted. No magic to it. I think it's just a matter of playing with the values until you get the shift amount you want, subject to the component tolerances and LED characteristics you have in your circuit.

73 Hans G0UPL

Re: 30 METER BEACON PHOTOS AND CAPTURES

"hanssummers2000"

#107

Hi Newt

I wonder if the results might be even better if this situation could be >avoided. Perhaps a balun between the TX and the dipole?I remember you showed some pix at the FDIM where you rigged up your TX while on holday. I believe that you had fasioned a balun between your TX and the antenna.Yes... for details of rhe holiday QRSS operations, see
 and

Can you describe how you made that balun?Yes... the TX has 5m of RG-58 coax directly from the LPF output to the balun. I used the same balun design I had used a few years ago in my junkbox beacon project, see this page:  . The actual design is from this page:  by N1HFX.

For my QRSS transmitter, I used exactly the same design except with a FT37-43 toroidal core, with 6 bifilar turns.

73 Hans G0UPL

Hans Summer's web page 30m transmitter

"Mike"

#106

Can anyone tell me the values of the voltage divider resistors biasing LED varicap in the schematic on this page? 

I think the upper resistor is 33k but have no clue what the grounded one is.

'QBH

Kits at Friedrischaven

"Stephen"

#105

Guys,

Just a quick note to say that I will be selling some of the second run of beacon kits at the Friedrischaven hamfest this Friday-Sun. I will be on the SDR-Kits stand  Its in the main Hall A1 stall E43.

The price will be 12 Euros if you pre-order your kit and provide me with your callsign so I can program your keyer chip before I leave home on Thursday morning. The discount is so i do not have to go through the process of programming the keyers at the rally - its always hectic!

If you buy on the day the price will be the regular rally price of 15 Euros. The additional 3 euros goes towards helping towards the cost of the stall.

For those of you who cannot make the rally please don't panic. We have enough boards and parts to meet our current and predicted committments and for those of you who have already asked for a kit to be reserved that has been done.

When i get back from my holiday, in the second week in July, I will post ordering details here.... Apologies for the delay. Hans and I decided that in order to streamline the process I would program the Keyer chips. So I installed the latest version of the WinAVR/AVR Studio Toolset on my Windows 7 laptop to start work only to discover that Hans had used an earlier version of the compiler and whilst the compilation was clean with the latest version of the compiler the code wouldnt "Beacon". It took us a couple of days to figure out that we needed to revert to the old version of the compiler rather than battle wit the source code. And to think I thought I had left all this stuff behind when i retired from my job in IT. In my day compilers had to cope with legacy code!

72/3 to you all,
Steve G0XAR (and Hans G0UPL)

--
It is vain to do with more that which can be done with less.

Re: 30 METER BEACON PHOTOS AND CAPTURES

"Newton"

#104

Hi Hans,

You wrote:
I wonder if the results might be even better if this situation could be >avoided. Perhaps a balun between the TX and the dipole?I remember you showed some pix at the FDIM where you rigged up your TX while on holday. I believe that you had fasioned a balun between your TX and the antenna.

Can you describe how you made that balun?

Thanks,

Newt
k0nwt

Re: 30 METER BEACON PHOTOS AND CAPTURES

"Paul Daulton"

#103

开云体育

You are correct there is some rf on the coax. Note the power box , the small one with metal plate. this has a type M coaxial power socket and an F connector, a 7805 IC drops the voltage to 5v. I can use any spare wall wart transformer with correct polarity and a plug that will fit.

?

I can touch the plate and see a slight bump in the signal on my own receiver. I will put a choke in each leg of the? power coax next time I take it down. Or maybe a bifilar wound choke.

?

Note also I drilled two 1/8 inch holes in the bottom of the tx box to drain any moisture out.

?

I regularly check the grabbers on the digilander site, so fara no DX. Our stateside forums dealing with the Lowfer beacons have developed a very good reporting system. I have 19 states confirmed on my 185.3khz beacon. Thats all the states where active listeners reside. I encourage all that listen to post screen captures, and where possible edit the captures in Microsoft picture viewer by adding the text of the calls received.

?

Check out our lowfer sites at and the lowfer mailing list on? ? click on side bar, email lists, and scroll down to "lowfer". I have been using the Argo and Spectran software chasing weak signals? on 137khz, 160-190khz and 13.555 to 13.565 mhz for about 9 years now. I've made lots of friends and had lots of enjoyment. It is a two way partnership between those who beacon and those who listen. A great learning experience.

?

73 Paul

Show quoted text

----- Original Message -----

From: hanssummers2000

To: QRPLabs@...

Sent: Tuesday, June 22, 2010 7:40 AM

Subject: [QRPLabs] Re: 30 METER BEACON PHOTOS AND CAPTURES

?

Hi Paul

> I HAVE CREATED A PHOTO FILE "K5WMS" WITH PHOTOS OF MY BEACON CONSTRUCTION AND INSTALLATION.

[Snip]

Congratulations on the success, the screenshots, and I'm glad you're having so much fun! I hope you will look for your beacon on the worldwide grabbers too and soon see some DX reception when the conditions are right!

One question I had... I see that you have mounted the PCB nicely in a box with hooks on the side, which look like they are designed so that the transmitter sits directly at the centre of the dipole... the dipole attaching to those two hooks. Then the coax brings power in at the "bottom" of the box (when it is hung on the tower).

I'm no antenna expert at all, but I wondered about something... The LPF output is designed for 50 ohms output so putting it at the middle of the dipole should be Ok. However one arm of the antenna would also be connected directly to PCB ground, which is itself connected to the coax power feed cable. This means that the coax feed cable would form effectively part of the antenna "dipole", unbalancing it and probably no longer matching it to 50 ohms.

I wonder if the results might be even better if this situation could be avoided. Perhaps a balun between the TX and the dipole? Or perhaps you could fit a couple of RF chokes at the two power connection inputs, to stop RF going back down the power feed cable?

Feel free to ignore me if I'm talking giberish, as I say, I'm no expert on antennas (or anything else, for that matter).

73 Hans G0UPL

Re: 30 METER BEACON PHOTOS AND CAPTURES

"hanssummers2000"

#102

Hi Paul

I HAVE CREATED A PHOTO FILE "K5WMS" WITH PHOTOS OF MY BEACON CONSTRUCTION AND INSTALLATION.[Snip]

Congratulations on the success, the screenshots, and I'm glad you're having so much fun! I hope you will look for your beacon on the worldwide grabbers too and soon see some DX reception when the conditions are right!

One question I had... I see that you have mounted the PCB nicely in a box with hooks on the side, which look like they are designed so that the transmitter sits directly at the centre of the dipole... the dipole attaching to those two hooks. Then the coax brings power in at the "bottom" of the box (when it is hung on the tower).

I'm no antenna expert at all, but I wondered about something... The LPF output is designed for 50 ohms output so putting it at the middle of the dipole should be Ok. However one arm of the antenna would also be connected directly to PCB ground, which is itself connected to the coax power feed cable. This means that the coax feed cable would form effectively part of the antenna "dipole", unbalancing it and probably no longer matching it to 50 ohms.

I wonder if the results might be even better if this situation could be avoided. Perhaps a balun between the TX and the dipole? Or perhaps you could fit a couple of RF chokes at the two power connection inputs, to stop RF going back down the power feed cable?

Feel free to ignore me if I'm talking giberish, as I say, I'm no expert on antennas (or anything else, for that matter).

73 Hans G0UPL

Argo tricks

"pgdaulton"

#101

One of the tricks you can use with ARGO is multiple screens, try and set one screen centered on beacon band, another up 100hz, and another 100hz below. You can set different gains and sensitivity and see which is best, just assign a different folder for each screen. I use &#92;desktop&#92;30mbcn(1,2,3) then put date on next pull down. Set for capture every 15 or 30 minutes and watch band changes.

Also note Spectran, Spectrumlab, and ARGO can run simultaniously on the same sound card.

Be an experimenter!

Paul k5wms

30 METER BEACON PHOTOS AND CAPTURES

"pgdaulton"

#100

I HAVE CREATED A PHOTO FILE "K5WMS" WITH PHOTOS OF MY BEACON CONSTRUCTION AND INSTALLATION.

ALSO INCLUDED ARE CAPTURES FROM KL1X/5 IN BARTLESVILLE,OK AND W4HBK FROM PENSACOLA FL.

I AM IN CENTRAL ARKANSAS GRID SQUARE EM34WU.

I ALSO HAVE BEEN COPIED BY MIKE WE0H IN ST FRANCIS MN BUT HAVE LOST THE CAPTURE. I EDITED THE CAPTURES AND ADDED THE TEXT.

THANKS HANS AND STEVE FOR A FUN PROJECT. THREE DOWN AND 47 TO GO FOR WAS!

PAUL DAULTON K5WMS

WE0H Grabber back again!!!

Mike-WE0H

#99

New server once again. Lets see how long this lasts before it locks up...

Mike
WE0H
EN35hj

Tutorial on programming AT Tiny chips

"Stephen"

#98

Good morning one and all,

For those of you who are interested in learning how to program the AT Tiny chip (we use the AT Tiny 13 in the beacon kit) there is an excellent tutorial at :-

It uses the AT Tiny 45 but the example programs will run in the Tiny 13.

The code for the beacon is available on Hans's website.

72/3 de Steve...G0XAR

WE0H Grabber new address...

Mike-WE0H

#97

As I figured would happen with a freebie website, they deleted my account tonight. No surprise there. So go to:

and lets see how long that Grabber survives. This is my pay per month site but it had issues with ftp service before, so who knows if it will keep working or fail.
-- 
Mike
WE0H
EN35hj

Re: NP0 Caps

Mike-WE0H

#96

I use that Lyle K0LR style thermistor crystal heater in my freq counter. It has maintained better than 1hz stability for over a year now.

Mike
WE0H

Charlie , W5COV wrote:

Show quoted text

 ...
I built my 10.140 MHz. oscillator on a very small board separate from the transmitter . I soldered a thermistor to the crystal to maintain a constant temperature . The entire board is then encapsulated in a small container and filled with thermal conductive epoxy .Only the leads for hookup to the transmitter come out of the package .
 I haven't yet had time to run many tests with it . I'll post my results once I can run it for a few days under different temperature conditions .
 Charlie , W5COV

Re: NP0 Caps

Matt Palmer

#95

NP0 caps become much more important when going cold... not such an issue for ham electronics which will likely never see temps below 0C

Matt
W8ESE
sent from my VIC-20

Show quoted text

On Thu, Jun 17, 2010 at 12:33 PM, hanssummers2000 <hans.summers@...> wrote:

?

Hi Steve et al

> Greetings from sunny England,

Speak for your own part of England! Here in London, the sun has disappeared behind some thick clouds.

> Those of you who have built the beacon kits will have noticed that we do not use NP0 caps. In fact I cannot remember the last time I used them. Yet these beacons are very, very stable in output frequency as are my other projects. Which makes me wonder if modern caps are much less temperature sensitive than they were in times of yore and question why people still use them.
>
> What do you guys think?

Personally I think NPO caps might be useful sometimes, but generally are over-rated. There are a lot of other temperature-sensitive parts involved in an oscillator, including of course, the crystal itself.

In past QRSS work, I have used the DB6NT crystal heater, see . I found that it completely removed any observable drift, even though I didn't trouble with NPO capacitors. So I believe that, in the case of crystal oscillators for QRSS, the main freuqency-drift-determining component is the crystal itself. The DB6NT crystal heater is very nice. It typically goes on an HC49 crystal, whereas the crystal in the QRSS Beacon kit is a 1/4 height crystal. So I'm not sure how well it would work, or maybe need adaption. Beware too, that it will cost you somewhat more than the QRSS beacon kit cost you!

73 Hans G0UPL

Re: NP0 Caps

"Charlie , W5COV"

#94

开云体育

I have to agree with Hans . NP0 caps are fine in some applications , but not all . I just changed a pair of them out in a filter and replaced them with some high quality "glass" capacitors , which work much better in this application.

?

I am on the waiting list for a beacon , but while waiting and having worked with QRSS60 for many years , know the crystal and oscillator are the areas of real concern .

?

I built my 10.140 MHz.?oscillator on a very small board?separate from the transmitter . I soldered a thermistor to the crystal to maintain a constant temperature . The entire board is then encapsulated in a small container and filled with thermal conductive epoxy .Only the leads for hookup to the transmitter come out of the package .

?

I haven't yet had time to run many tests with it . I'll post my results once I can run it for a few days under different temperature conditions .

?

Charlie , W5COV

?