Those of us in N Europe suffer from qrm on AO51, southbound from the poles, from fm transmitters thought to be in N Russia.
I have just come back from China, where thanks to Michael and others, I met the Shandong ARS in Jinan. Amongst other hospitalities, the group took me to a street selling handhelds as well as other stuff like mobile phones, mobiles and I think repeaters.
There I bought a VHF handheld for 180 RMB, about £12 UK or $26. (Including battery, charger, belt clip and antenna!) This promises 2.5 W out into keyboard entry and/or stored channels, either simplex or separate tx/rx. The model has the PU HUANG brand name, model PG5118 and covers 140 to 170 MHz, no tone or ctcss. The keyboard entry will only accept 5khz steps.
The company name is Guang Yuan Electronic Co Ltd; I can't read the address -it's in Chinese - but was told it was made 100km from Xiamen in Fujian province.
The instructions offer bands as follows:
145-175, 150-170,136-`74, 200-270,400-420,430-450,450-470, 400-470 MHz.
Other handhelds on sale in Jinan covered 70cms and the 145-175 and 450-470 MHz bands - these were more common.
In Beijing at the Silk market (4th floor) there were a few stalls selling "Walky talkies" with the same frequencies, and they recommended a "Chinese Kenwood" that looked like my Pu Huang but had Kenwood written on it instead. They had other "Kenwoods" and "Motorolas" but your guess is as good as mine.
Another name is Bei Feng (BF) and their address is:
Also in Beijing I got hold of some flyers for the HONGO range produced by the Fujian Quanzhou Hongda Electron Industry Ltd.
HD-45AT : 136-174, 400-430 0r 440-470, 4/5w, ctcss, 12.5 khz channels. A-88: : same bands, 2.5w, no ctcss, 12.5 khz channels. HD-8800:400-470,no ctcss, QT/DQT (don't know what that is),5w, 12.5 khz steps.
What's all this got to do with AO-51, well the box my Pu Guang came in is written in Chinese, English -and Russian. The Russian reads "Seriiniaya osobennaya vnutrisvyazhaya sistema" (I'm transliterating from the cyrillic) which reads something like "serial personal home system" - I'll get a better transaltion from my Russian tutor tonight.
So I conclude that these sets are being sold on the Russian domestic market - why else write in Russian on the box? And they are therefore a strong candidate for the FM uplink qrm on AO-51 when the ctcss access is off.
Finally, looking at all the above specs., while some of them do have ctcss, and they could have 5 or 12.5 or 25 kHz steps, none have the odd 6.25 kHz steps. Maybe future FM sat builders could get around unintentional qrm this way?
If anyone wants a scan of the "manual" or flyers please email me off the list.
73 de andy G0SFJ
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