HG50MHZ

At 9AM on 15 August 2011 we arrived at Szechenyi-hill OMK telecommunication and broadcast station of Antenna Hungaria to set up our station on the ground level of broadcast transmitter building. We connected a 50ohm load onto the 32 radiating element antenna and measured with an SWR tester if any RF were present but fortunately no signals were detected so we connected the broadcast antenna to our FT847. We had an S3 level white noise but no video signals from the operating Nagykanizsa O1 transmitter. We were happy because we would surely not make interference to television viewers with our 700W power. Tuning out our ACAM 1000 to the broadcast antenna the SWR was just perfect 1:1 without measurable reflected power. We made a short test with HA5OB Zoli from Budapest downtown and his 5W transmitter made an unbelievable S9+20dB strong signal strength and confirmed that our transmitter was clean in spite of S9+60dB on his FT817.

Though we were set we did not start operation because Antenna Hungaria invited us for a short memorial ceremony. At noon the director of Tivadar Puskas Telecommunication High School dr. László Horváth HA5PTL showed us a video how the television transmitter was closed down 12 hours earlier. Then Dr. György Tormási and Dr. László Falus HA5PE former engineer managers of Antenna Hungary, who are on pension today, summarized half century long history of television broadcasting. Dr. Tamás Holman HA5PT reviewed six year HA amateur history on 6m and the magic band features why 50MHZ was better for ham radio operation than for television broadcast. Mr. Andras Toth, communication director of Antenna Hungaria finished the ceremony summarizing milestones of analog to digital transition and shared with us company’s vision about future terrestrial television broadcasting. Then guests were showed the switched off transmitter and the HG50MHZ Special Event Station. And finally we started our four day operation.

According to expectations we heard local stations extremely well. The most contacts were made by Hungarians and from neighbor countries justifying the radiating pattern of the broadcast antenna.  Altogether we made 666 QSO from 37 countries and 127 pieces 1 by 2 degrees squares, all over Europe. Inside a 500km range we completed 279 Hungarian, 32 Slovakian, 33 Czechs, 25 Austrian, 25 Slovenian, 21 Croatian, 15 Serbian, 11 Romanian and 1 Ukraine contacts. Of course our radio signals did not stop at 500km but we reached
stations up to 2000km range.
We had unsuccessful EME sked and we tried also MS JT6M digital mode but without usable reflections. We had two propagation modes to achieve long distance DX contacts, tropospheric ducting and sporadic E. In the mornings the level of E layer ionization was still low but our signals were well copied in a 1000km range with tropo ducting, and additionally we saw comments in DC Cluster that MS made HG50MHZ signals loud in short bursts. This happened because of our high power and the very effective low angle radiating antenna system.

However, we hardy copied low power stations because our unidirectional antenna collected much noise from every direction and we were straggling with understanding weak signals covered by high noise, we had a feeling to communicate with only high power stations. In the afternoons we had short Es openings that provided additional experiences. Normally strong stations were weak now and we were surprised because with G4DEZ and some other stations we exchanged only 55-57 reports. We thought that our antenna having a narrow disc shape characteristics transmitted our high power just below the E cloud and our energy was ineffectively reflected by E clouds 300-500km away from us. We had several occasions that our low power friends inside Budapest made more contacts than us additionally they helped us to correctly log call signs that we hardly understood.

On Wednesday evening we discussed the strange phenomenon and we had an idea to compare broadcast antenna with a Yagi beam. We asked permission from Antenna Hungaria and they allowed installing a Yagi in the garden. On Thursday noon we erected a five element DK7ZB Yagi and we were lucky to have Es opening right away. The first CQ call was answered by IS0/IK1ZZN from Sardinia Island and then IZ1CBQ from North Italy by 59/59 with his whip antenna and 2W transceiver. We were happy to work a QRP station and then we wrote lots of stations into our log that we could easily reach with the high radiation angle and low noise Yagi antenna. It is very likely that we wouldn’t have copied most of them with the broadcast antenna. The final statistics of HG50MHZ contacts: http://www.ha5hrk.hu/files/hg50mhz_wkd_squares_and_DXCC.pdf

We had fun and learned new experiences. Thank you for management and employees of Antenna Hungaria for their support and hospitality. Thank you for experts of Information and Telecommunication Authority granting our special event station with appropriate permits for this historical event. We all enjoyed being part of HG50MHZ team where everybody contributed with equipment and knowledge in order to enjoy together with the international 50MHz community the noise free conditions of six meter band in Budapest and its vicinity.
 

Thank you for QSOs that we confirm electronically through LoTW and eQSL.cc and by direct QSL cards if needed. We wait your QSL cards on this address http://www.qrz.com/db/hg50mhz We appreciate all QSL cards and SWL report together with a SAE (Self Addressed Envelop) but USD bank note or IRC is not required.

73 es DX de HG50MHZ: HA1YA, HA2SU, HA2UF, HA5AO, HA5BBM, HA5JI, HA5OB, HA5OT, HA5PT, HA5SE, HA5TI, HA5TMK, HA5UK, HA5UY, HA5XA, HA7PL, HA7RY, HA8MT and HA9PP

The summary documentum is downloadable: http://www.ha5hrk.hu/files/HG50MHZ_summary.pdf

HG50MHZ went QRT last evening and we left the TV-tower.

We had a truly exciting four day activity. We would like to thank everybody who made a QSO with us, called us, were listening or were just following/visiting our website. We greatly appreciate all reception reports, comments and stories. We also thank all the staff of Antenna Hungaria for their generous hospitality, the National Media and infocommunications Authority of Hungary for their support with licensing and everybody who made this activity a reality.

It is now time for us to summarize our experiences. We will shortly share our thoughts with you on these web pages, where we will add pictures and more. So please keep checking back.

73 from the HG50MHZ team.  CU on the magic band!

We have made about 370 QSOs so far. Propagation is far from being the best, Most QSOs are being made using tropospheric propagation and ES is quite weak /but read further/. We often get very good reports and we are very happy to see the great interest from stations around the world to work us.

We have to admit, we are not copying stations very well. We are trying to enhance reception, but we are not truly succesful with those attempts.  We get some comments on the cluster, like “please turn your antenna to me” and the like.
Given that we use the antenna system of the TV-tower, we can but smile at these comments. We have no other antenna here than the system that was used for broadcasting the TV program until Sunday, and it would be too difficult to turn the nearly 200m tall tower.
The antenna system is omni-directional. It was designed for transmission to the neighbouring area. Consequently, it was not designed for DX and was not designed for RX. Our radiation angle makes the system fantastic for broadcasting locally using tropo, but not very effective to utilise ES openings. Also, we are beaming somewhat downwards to cover the entire city at the foot of the hill. This has the effect that we also get a good amount of noise from he city… And of course there are several other transmitters on various frequencies working in the building. We use a band filter for cutting signals but those on 50 MHz, but still there is some band noise. We have experimented a littlebit by unpluging that half of the antenna which is pointing downhill. We have found however, that this reduces the antenna gain significantly and although noise becomes lower, stations are also coming weaker. So we are now using the complete antenna arrangement again.

Even more disappointing is what we hear on the earphones. People have told us and we ourselves have verified this: sometimes our callers are crystal clear on the audio stream we are sending on the Internet, but the operator of the station simply cannot copy.
We are still somewhat puzzled over this phenomenon. True, we have a lot of local noise in the room, which we share with the cooling systems of the still operating TV/radio transmitters. This humming noise of the fans and airconditioners might phase out signals from our headphones? Today we installed an AF DSP unit, but it is tricky to use. This DSP (TNX, HA7PO!) sometimes helps, but at other times it only makes us even more deaf… We will try to experiment a bit more, but please bear with us.

The operators at the radio would be very glad to make as many QSOs as possible. We do not mind dupes, so even if you have multiple contacts with us, please just call in any time you hear that we are not busy handling pileups. Let the log fill quicker!  :)

Sorry, this entry is only available in Magyar.

This video – which unfortunately is available only in Hungarian) – records the moment when the old historic TV transmitter was switched off. The video is also a ‘guided tour’ around the station, wo it maybe an interesting watch even for those who do not understand Hungarian.

We are grateful for Puskas Tivadar Tavkozlesi Technikum for permitting us to use their video on our website.

Jo, OE4VIE has recorded our SSB QSO and posted it on YouTube.

Thank you for the QSO and the video.
We encourage everybody to send us their recordings and SWL reports. It is interesting to hear things from the other end!

Following a short memorial ceremony and a guided tour of the – now silent – transmitter, HG50MHZ became QRV. About 60 QSOs are already in the log. You can watch the live video/audio stream on our website or contact us using the chatroom.

We are already at the QTH, working on the setup. HA5TMK is doing the antenna cabling, HA5PT is assembling the RIG and setting up the computer. HA5OT is working on the computer network and the online video streaming. Antenna Hungaria staff and HAMs working here are very helpful and help us get whatever we need, so we hope to get on air shortly.

http://www.youtube.com/watch?v=0pktdjnngiI