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Hi Re the Hans Summers 80m TX (and posibly other versions) Tom ZL1THG was unable to get his 80m TX on frequency . He bypassed the inductor with a short, leaving the tuning capacitor remaining.He still was at 3500.600 kHz... This wasnt unexpected. I assume that these crystals supplied are cut for oscillation with a 30 pf load. Circuit components should give this load to acheive the rated frequency on the crystal. In this case 3.500 MHz or 7.000 MHz,, 10.140 MHz However the frequency we want is nominally 850 Hz higher on the 80m and 40m bands. So the capacitance needs to be smaller than 30 pF. Tom succeeded acheiving oscillation on 3500.850 kHz, by using the existing trimmer and an 8.2 pf instead of the toroid inductor in the VCXO. Depending on the crystal a larger or smaller capacitor may be needed Kevin ZL1UJG

PS. He acheived 320 mW at ~ 52 mA PA current with a 13v PSU for the 2N7000. About 50% efficient Kevin ZL1UJG

Dear all I have my 40m qrss beacon running now. Acording to my trusty meter, it is on 7.000.81 Any reports will be most welcome Thanks Tim VK4YEH

Hi, One of the fellow QRSS'ers in Hamilton while building the 80m TX, noticed a small problem. To achieve frequency he had to remove the inductor in series with the crystal, not unusual. He replaced that with a small? fixed capacitor (4p7) to get the crystal tuned on frequency. He noticed a start up?problem, which is probably due to the small values of capacitor in series with the crystal. I suggested that he put a 10nF or 100nF across the collector resistor of the oscillator. This worked well. I suspect the negative feedback of the unbypassed?collector resistor was causing marginal operation Kevin ZL1UJG

Hi, I have heard others mention that they had low power from their Hans Summers TX. Well one my fellow QRSSers in Hamilton has that exact same problem with his 30m one(after being modified to 12v PA operation) He has some test equipment and did some tests. The 12v modification allows for ~ 320 mW (+25 dBm) output for around 50 mA current, and he stated that he had around +150 mW (+22) about 3 dB down from expected output level. He seperated the 1nF from the PA. Its actually 10nF or 100nF in his one. He attenuated the power and measured oiutput power from the PA without filters to be +25 dBm.(This was measured with a Spectrum Analyser, with careful verification first. Mmm. I had told him that the filter is essentially 3 seperate filters so he connected the input C (270pF) and L (1.1 uH) to the output C 270 pF. Still low by 3dB. He took turns gradually off and the power returned. He then did the same for the other coils and reconnected it up. And about 320mW, with harmonics 50 dB or greater down. Even though the Toroid coil turns have been reduced, we suspect that they arent the problem. We will keep you posted on the results of further tests as they come to hand Kevin ZL1UJG

If you have a look in the photo section under VK5DJW there is a capture pic... if it is a ZL1 I would like to know the power output :) -Dan VK5DJW

Apologies...It is a typo... I mean 10.140030 - 10.140040MHz -Dan

Hi Guys, In case any one is interested I am transmitting continuously QRSS3 callsign VK5DJW tonight on 10.0035MHz Power is about 100mW -Dan VK5DJW

Hi everyone! Finally today on air, after Hans G0GPL kit 30m QRSS , and amended in accordance Aldo Iw2DZX I thank them both for the opportunity ' fun! My beacon 'set at the 10.140.04 Mhz frequency of about 100 mW of power, the antenna and now 'a dipole positioned towards E- W for physical reasons of space, but a vertical dedicated 'already' under construction! I would appreciate it if someone were to listen to my signal Please e-mail to see if any adjustments are to do or variants, as with autocode Argo known that the signal and 'a little' distorted, but I need to look for the cause of your relationships! Thanking all in advance for your cooperation I wish you good listening and good DX to all! IK6ZEW op. Fabrizio D'Alessandro JN72CK Pescara Italy email: ik6zew@... QSL via qsl.cc

It looks like I've set the world on fire - or at least a few Knights! Thanks for the feedback. To answer a few questions: The details of my receiver can be found in my design entry at: http://www.circuitcellar.com/nxpmbeddesignchallenge/winners/HM3871.htm I am however further developing the software including improving my test server application. The receiver sends raw sample data. This is currently IQ sample data at about 600SPS, but there is some work needed to optimise this - sampling rules indicate it could be a lot lower. I think it works out to about 3.5GB per month, which could be an issue for those of us with data limits (which is the usual case here in Australia). I think there is still plenty of scope for data compression to keep the traffic down. I don't think the CPU would have the processing power to perform the actual FFT operation. My intention was to use a VPS (virtual private server) service to host the network. Some of these services are available for <$10 per month. I have yet to follow up with such services to see if the system is compatible. A donation button on the website would help fund the system. However the network is not something I can tackle alone. As much as I'd like to, I'm current knee deep (or more like neck deep) in KiwiSAT development so my spare hobby time is limited. I can probably address the design and firmware needed for the receivers, but someone to help with the server is needed. My idea for data presentation was a web pages with rows of images (one per receiver) showing activity over the past hour or so. Smaller images would be shown by default, with the option to enlarge for more detail. If we have a large number of receivers we could have limited stations shown on the home page by removing locations that are near each other. The server would also have the ability to manage receivers, including the ability to upgrade firmware. Receivers can therefore be set and forget in operation. I still have a lot of unanswered questions and ideas, but if there are a few people interested in helping build such a system, I'm willing to do my part and make it happen! Clayton

Hi All, I am currently transmitting My call sign (VK5DJW) in QRSS3 from an inverted V dipole I set up the Hans Summers QRSS kit today using a calibrated frequency counter at work. it was a Racal Dana 1992 if anyone is interested. Would appreciate if anyone lets me know any reports. if they have a chance. I will leave it on and check out some nearby grabbers. -Dan

Now I'm on air for a few days, I'm testing the station. Reception reports are welcome, you can e-mail me a screenshoot of the reception and other information about your radio station. I thank you very much for your information about my weak signals.Actually position towards dipole is N-S, at power tx is 100mW +/-!! ik6zew@...

Hello Knights! ? I didn't get much response to my email last month, but I'll try another tact before giving up. ? For a while I've had an idea of developing a server system with remote 'thin' receivers around the world. These receivers would send in their sample data of a narrow QRSS band to the server, which would then generate a worldwide view of the signals being grabbed. Data could also be logged and overlays generated etc etc - it is kind of like the WSPR net but for visual MEPTs. At minimum it would allow for a worldwide instant display of activity with the ability to roll back in time. ? Anyway I implemented the 'thin' receiver for a design contest, and got among the winners. Subsequently the magazine (Circuit Cellar) has asked if I'd like to turn my project into a published article. As I'd get paid for this, it could be a source of seed funds to make the QRSS network a reality. ? The real question though is do the Knights think such a network is of value, or do you find the aggregators and ad-hock grabbers sufficient? Personally I found it inadequate when I was running my MEPT, but this is in part due to the solar power and low duty cycle of my MEPT - I had to watch at just the right time to see it. ? The other benefit of the network is the ability to expand the grabber base. As the receivers will be cheap (I think the component cost can be as little as $50) and not require a PC or anything (only a power source, antenna and internet connection) more operators should be able to install them. ? What do you think??? ? Clayton VK1TKA/ZL3TKA

can anyone point me to a source? Thanks, Stan ak0b

Hi folks Just getting back into ham radio after a 16 year break. Having fun using my recent build of an MKARS80 into a half wave dipole. Not familiar with most of the ham radio software but need a decent virtual logbook... Any recomendations or what do you use? Thanks Regards Philip G4JVF

Hi Guys, I am sorry that some kits have been out of stock for a little while and that some orders have gone missing in the post. A rush of orders from Sweden depleted stocks and I had to go away at short notice on family stuff which delayed restocking. My apologies for this.? The good news is that 200 PCBs arrived this morning and I have sufficient stock to kit 40 and 80 meter beacons within the next couple of days. I am awaiting 1,000 30 meter crystals from a supplier in the USA. I hope they will be here in the next 2 weeks then I'll kit 30 meter beacons and send out the kits for those people who changed their orders to 30 m beacons.? The postal service here is normally pretty reliable. But just lately some orders have been lost. If your order does not arrive please get back to me and I'll ship you a new one and seek compensation from them here.? Hans is currently working an 80 hour week so has little time to devote to developing the RX kit. Watch this space for future announcements about it.? Thanks for your patience. 73s Steve G0XAR -- It is vain to do with more that which can be done with less.

I would like to share ideas on packaging. I am in the process of building a qrss transmitter which I will put into a square glass bottle I obtained from Lobby Hobby. The bottle mouth is 2 inches and the holding area is 3 inches high. It has a combination aluminum and plastic lid. I plan to use an F fitting for the antenna connection. Much cheaper than BNC or UHF and they work very well it crimped correctly. I have mixed feeling about if I will use a heater on the xtal or not. Since the entire board would not be in any draft condition. I am also thinking about filling the bottle with glass beads after I install the transmitter. Makes a good heat sink I think. Can not decide if I will paint the inside of the bottle black or not. I am considering the inside black with the outside silver. All power supply components will be outside the bottle and may or may not be on the top of the lid. Initially will not be on the lid. I will add a wood box with the pink foam installation between the bottle and the wood. I long term goal is to build something super stable and to bury it in the yard. Interested in your thoughts and suggestions, Thanks, Stan AK0B

Guys, My apologies for the delay in the production of the 30 meter kits. The reason was that my normal supplier of 30 meter crystals could not supply any more. However, thanks to the efforts of my good friend Paul AK1P, we got some custom made in the US. This took a while but I am happy to say we now have stock. There is no need to rush, we have plenty and, thanks to Paul, we got a really good price so there will be no price increase. I will be sending out kits for those of you who ordered 40 meter kits and asked for them to be changed to 30 meters next week. Tomorrow, I'll be stuffing parts in bags for 30 meter kits and you should be able to order kits and crystals from the shop from the beginning of next week... 73s Steve G0XAR

If you can it is always worth measuring the inductance of a toroid core rather than relying on the various charts and on line calculators that tell you how many turns equate to an particular inductance. I was making an LPF for 20 meters the other day and discovered that the chart I was using told me I needed 17 turns for a particular inductance, however when I measured the inductance I only needed 15 turns. With the extra turns the LPF would not have performed as required.... 73s Steve G0XAR

Hi Guys, We now stock crystals for 14.000 Mhz and shortly will stock some for 28.000. 73s Steve G0XAR