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The LSWC 2018 Construction Contest

Arduino, Contests, Home Brew No Responses »

Dec 042018

Wednesday 21st saw the LSWC hold their annual Construction Contest for the Joe Rose Memorial Trophy. Last year saw us two different versions of ATV transmitter. One being for home use including a partly assembled water cooled power amplifier (For an update see below) built by Adrian M0NWK. The second, and also the winner for last year, being a fully portable transceiver in a case built by Jason G7KWP.

Adrian M0NWK

This year Started off with a similar theme. Adrian M0NWK, started off by showing us his Arduino powered controller for a comtech 23cm ATV transmitter.

This was achieved by removing the dip switches from the transmitter and replacing them with a SSR (Solid State Relay) board. These relays are then controlled by the Arduino which also shows the selected frequency on the front LCD.

Adrian also showed us the completed Water Cooled Power Amplifier which was shown the previous year. Also shown was an Arduino controlled Temperature monitor.

Andy G0FVI

Next up was Andy G0FVI. Who has constructed an 80m CW receiver which will eventually become a transceiver in time. By choosing an IF of around 10.695 this allowed him to use bits from numerous scrap 11m radios he had laying around.

The bandpass filter was fabricated from two Toko type ferrite core coils.
The first mixer is based around an SA612 chip and also provides amplification. In retrospect this may have been a bad idea as the chip does produce a few ‘birdies’ although they are well below main signal level.
The VFO is an Alan Lake design for 80m with the L/C of the tuned circuit changed to give an output of 7.2-7.1 MHz. Output is buffered in the VFO enclosure and this is fed to the 1^st mixer.
Output of the 1^st mixer is fed to a 10.7 MHz XTAL filter with a bandwidth of about 15-20KHz.
The IF amp is based around an MC1350 IC. Negative DC feedback from following stages provide AGC action (fast/slow).
Demodualtion to provide audio out is achieved using a diode ring mixer. Such a mixer provides a nice clean output with little spurious signals. A 10.695 MHz signal is fed into the ring mixer (together with IF).
Demodulated audio is fed to a 2 transistor pre-amp which also provides DC feedback for AGC. Audio is sampled at this stage and fed to another transistor amp to drive the signal meter (taken from an 11m walkie talkie!).
The audio stage is based on a rather ancient LM380N!

All stages were built and tested using a sig gen/scope etc. before being connected. Great care was taken with the construction of the VFO, whose spectral purity I was finally able to look at using an SDRplay RSP1A and a beta release spectrum analyser app.

Controls are IF (RF) gain, volume, RIT, AGC fast/slow and VFO.

When I complete this I will add a prefabricated board for PA and some TX/RX switching (should just about fit). I will sample VFO and mix with TX XTAL oscillator, add some filtering and off to PA. Might be an idea to have a go at matching XTAL filter in the receiver too.

David G6MAF

Next up was David G6MAF. Who had constructed a RF tap, or signal monitor which covered 2-30MHz. A device like this is very useful for monitoring your own transmissions by connecting straight into the feed line. With 50 ohms through to the antenna from the transmitter, a second output is taken and attenuated for feeding into a device such as a spectrum analyser etc…

Bob G4PDF

For the final item we made full circle as Bob, G4PDF, showed off his portable 5GHz ATV Transceiver. The equipment was all installed in a box which was mounted to the back of the dish which was then fixed to a tri-pod. The transceiver included a screen overlay showing his Callsign and also converted a received GPS signal into a locator which is also displayed.

The Winner

It was at this point after all had builds had been shown that contestants left the room for the remaining to vote on who’s they thought was the best. After discussions about complexity, imagination, modules or scratch built & uniqueness, the vote was in.

The contestants were called back in and the Winner was…… Bob G4PDF, with his 5GHz ATV.

The trophy will be awarded at the clubs AGM.

FirPark Wings & Wheels

Special Event Station No Responses »

Sep 032018

LSWC was once again at the FirPark Wings & Wheels event. The Club was there from Friday afternoon through to Monday evening of the August Bank holiday weekend.

Friday

Friday afternoon Les G1LQB, Peter 2E0FGA, Stephen 2E0SSM, Steve M5ZZZ set off for FirPark from their various starting locations. Les arrived first and started setting up and putting the masts up, the great thing about the masts we use are that they are designed to be erected by one person.

In addition to previous years Steve brought down his 2m / 70cm beam and along with Les’s special rotator, aquired at a previous FirPark event, we had 2m / 70cm SSB available using the icom ic-910. We also had the usual fan dipoles covering all of the HF bands and Les’s X30 collinear for 2m / 70cm FM.

By Night fall on the Friday the antennas were ready to lifted into position in the morning for operation to begin.

Saturday

Saturday morning saw the antennas raised into position and operating began.

Image thanks to Les G1LQB

Some contacts were made using various modes, Including CW, FM, Via Satellites and SSB on HF and 2m. One of which being an SSB contact to America. We were also joined by Mick, M6OYP and his dog for the morning.

2E0SSM working satellites. Image thanks to Les G1LQB

Pam G4STO also joined us and brought with her the usual sausages and burgers, although an unfortunate dog incident occurred with the burgers, and cooked us a late breakfast and then some lunch. We were also joined by Barry G4DBS who spent some time on the radio.

During the day we had a number of people come and speak to us with a couple taking away Foundation books and some magazines. We hope we will hear from them again to do there Foundation licence.

As the day come to an end Les, Stephen and Peter were left to camp over and were treated to a nice sunset.

Sunday

After a chilly night the three campers arose on Sunday morning ready for another day.

Sunday we were joined by Tom G4OSB, who took up the key on HF making a few contacts in the morning. By 11am though the weather had turned and the rain began to fall. The public had left and some stall holders had packed up and headed for somewhere warmer. Les, Stephen, Peter, Steve and Tom braved the weather before Tom and Peter had to depart leaving just three to continue. Band conditions started to improve with some good contacts made two of which to other special even stations in other parts of Europe.

Monday

Soon Monday arrived and reading a post on the internet Stephen read that the digipeater on the ISS was surprisingly back up and running. So to see if this was true he got out his Tape measure Yagi and hooked it up to his handheld radio. Using the built in TNC / APRS he transmitted the packets not expecting to get a reply.

2E0SSM working the ISS with APPRS. Images thanks to Les G1LQB

After just his second transmission he got a reply back acknowledging his message and once the pass had finished he checked the received calls log on the internet and was delighted to see his callsign listed.

As the day went on we were joined for a brief period by Roger G3PVU & Jackie. Conditions on the bands were still quiet with mainly UK stations on 80m with one or two further afield on 40m. With the weather being better the other stall holders returned and so did the public. More people come to ask questions and see what was involved. As the winds picked up it was soon just Stephen, Les and Steve remaining but when Steve had to head off for other reasons Les and Stephen decided it was time to pack up and head home.

Next Time

The LSWC will be back at FirPark with some potential improvements to the station there being worked on next year.

Boultham Park Summer Fair 2018

Portable No Responses »

Jul 172018

This weekend was the Boultham Park Summer Fair and the LSWC was there as usual with a demonstration station.

G5FZ/P

out portable… again? Yes it is.

With equipment being collected during the week, Les G1LQB, Steve M5ZZZ, Ian G4EVK, Barry G4DBS, Tom G4OSB, Fred G4HNQ, Peter 2E0FGA, Roger G3PVU & Jackie were on site early Saturday morning. Soon Stephen 2E0SSM arrived to help during the day closely followed by Peter, M0EJL and Pam, G4STO with the tables and radios. All then helped in getting the station set up before the Public arrived.

Once everything was set up Pam got the bacon out and made us all some bacon butties for breakfast. Pam was also well prepared at dinner time with a large supply hotdogs which she kindly cooked for us all. A big thankyou to Pam for the effort she puts in keeping us all well-fed in addition to the many other things she does.

With the station up and running it didn’t take long before it was agreed that the new antenna, the Gap Eagle in the images above, was a worth while purchase as we were soon making good distance contacts on HF. A good contact to Bolsover on 2m was also made using Les’s small collinear.

With temperatures rising any piece of shade was a needed place to be with the rear door of Les’s van providing just that.

G4EVK trying to check his camera in the bright sunlight

We were also joined by two SWL’s, Lyon and Liz, who are currently studying for the Foundation course. Les, the clubs trainer, took an opportunity during a quite period to start some of the practical’s required for the foundation exam. With the help of Stephen, 2E0SSM, who was out wandering round all the stalls with a handheld, their first supervised 2m QSO was made and signed off.

Liz and Lyon listening and learning with their Baofang’s

At about 3pm the show was treated to a flypast by one of the BBMF’s Hurricanes.

By 4pm it was time to get packed up and squeeze things back into the van.

Fir Park Wings and Wheels

Reminder to all, LSWC will be out again for the August Bank Holiday 3 Day, 25th – 27th, Fir Park Wings and Wheels event. In the mean time remember the club meets every Wednesday evening and Saturday mornings.

So until next time….

VHF National Field Day

Contests No Responses »

Jul 142018

Last weekend, 7th-8th July, the club put on a station for VHF National Field Day.

The intention of this weekend was to have a social weekend for all members and to allow those who have not participated in a contest, me being one of them, to try things out in a relaxed and chilled manor.

Setting up G5FZ/P

After Preparing equipment on the Wednesday before, Les G1LQB, Stephen 2E0SSM, Alistair M0TEF & Steve M5ZZZ were down early on the Saturday morning to load up the equipment.

Once ready, the team headed up to the old RAF Scampton bomb dump where most of them would be stationed for the remainder of the weekend.

Fitting Antennas to the mast

On Arrival we were soon joined by Fred G4HNQ & Peter 2E0FGA. The first task was to get the antennas mounted on the mast and the mast winched up into position. One thing that should’ve been done before raising the mast would have been to test the rotator. Unfortunately we all forgot until the station was set up, only to find the controller we brought didn’t work. Fortunately, with the shack only being a few minutes away, Stephen rushed back to search for another one. Returning a few minutes later with a replacement and the station was ready for TX testing. It was found that the log-periodic that was brought gave a high SWR on all bands and it was suspected the Coax to be at fault as it had not been used for a while. The 2/70 beam however worked perfectly.

Les Setting up the Camp

The Portable station for the weekend

The setup team, minus me behind the camera

Time for Operating

After a few QSO’s were made to test the setup all was ready for the Contest to start.

The contest soon got underway with various people taking the hot seat in front of the radio.

As the day progressed the contacts started to come in and as the conditions improved one contact was made with a distance of 700km on 2m. Who says the 2m band is for local contacts only?

As the sun set the radio was kept in use until late into the evening. It was at this time that Stephen & Peter had to head home leaving Alistair and Les to man the night shift.

After some sleep in cars and tents Pam G4STO stopped by to provide breakfast. before heading off. Switching on the radio Alistair heard a station calling DA0FF. After checking the logging software to find we hadn’t had them before he started calling back. After battling the conditions the QSO was completed at a grand total of 786km. During the morning Fred G4HNQ returned and helped pack away.

Throughout the weekend there was a constant battle against the flies and bugs especially while we packed up on the Sunday.

After getting the equipment back to the shack everyone headed home worn out and sleepy from the enjoyable weekend.

The Grand Total at the end of the weekend was:

2m, 62 Contacts with a total of 21,675 points.

70cm, 15 Contacts with a total of 4,408 point.

The log submission deadline is in a few days so we will have to wait and see where we end up in the tables.

2m QSO Map

70cm QSO Map

With Such a successful weekend the club intends to put on more events like this in the future so keep your eyes pealed.

LSWC BBQ Night

Uncategorized No Responses »

Jun 302018

This Wednesday, 27th, saw the LSWC host another BBQ night. These are usually well attended and enjoyed by our members.

With Members arriving the BBQ was fired up and out came the burgers and sausages. We again must thank Pam, G4STO, for getting the food for the evening event and as always it was well enjoyed all round. I for one, was rather full up by the time all was eaten up. Especially when all the sausages and burgers were gone out came a selection of cakes for pudding.

With a cooling breeze and the sun setting a select few remained outside to make the most of the good weather with others in the shack operating between servings.

Pam G4STO preparing the Food

More Antenna Work

Antennas No Responses »

Jun 192018

This weekend members undertook more work on the clubs antennas. After the work done previously installing the HB9CV, when the mast was put back up it was found to have a high SWR. The coax used was an existing run that was previously used for 23cm which was taken down that same day with suspected antenna problems. With this coax now being used to feed the HB9CV which was also showing a high SWR the coax was now also suspected as faulty.

This Weekends Antenna Work

Stephen (2E0SSM), Les G1LQB, Peter (2E0FGA), Roger (G3PVU) & Steve (M5ZZZ) arrived on site Saturday morning and soon had the mast lowered.

Antenna Mast Lowered

With the mast now down again a new run of coax was installed and connected to the HB9CV. The spacing between each of the antennas was also improved.

With this done it was decided to remove the connector from the end of the suspected 23cm coax to check for water ingress. What was found was as predicted, water had got into the coax and had started to corrode the braid, center core and the pin of the N-type connector.

About 2ft was cut off the end to try and find some ‘good’ coax. A new connector was fitted, The 23cm antenna refitted with a second hand dipole and the mast was lifted back up. Both the antennas were tested, the HB9CV worked perfectly and its front to back performance demonstrated with an S9 signal completely gone when turned even 90 degrees away. The 23cm unfortunately still didn’t work and so further investigation is required. Next plan it to test the full length of coax with a dummy load to see if it all needs to be replaced.

GB5FPS Fir Park June 2018

Special Event Station No Responses »

Jun 192018

GB5FPS at Fir Park.

LSWC put on a special event station, GB5FPS, at Fir Park during the weekend of 9^th/10^th June.

The setup of two Fan Dipole antennas and Verticals allowed use of a wide range of bands from 160m through to 70cm’s. Numerous contacts were made over the two days both on HF, SSB and CW and on VHF/UHF FM. A number of satellite contacts were also made using 2m’s (Downlink) and 70cm’s (Uplink) simultaneously. A pleasant surprise came from a visit from someone on the Sunday who we had made contact with via Satellite on the Saturday.

In addition to radio activity we were treated to model aircraft displays and then the ‘real’ thing when light aircraft landed; took off and then performed a few acrobatic movements.

Helpers and visitors over the weekend were Stephen 2E0SSM, Les G1LQB arriving on Friday to start setting up; they were joined Saturday morning by Pam G4STO, Barry G4DBS, Tom G4OSB, Fred G4HNQ, Neal G8ZHL, Steve M5ZZZ, Jim G0EJQ and Stewart G3YPS. On Sunday Roger G3PVU and Jackie called in to lend a hand.

Here are some images taken during the weekend.

The Club will be at Fir Park again on the 25th – 27th August for their Wings and Wheels Event. Add it to your diaries as it’s usually a good long weekend.