ATV transmission from N6QQQ on K6BEN-ATV

Transmission recorded from output of K6BEN ATV station repeater. Nick N6QQQ was able to achieve uplink using a Mobicomm 80mW 1.2GHz ATV transmitter feeding a DownEast Microwave linear amp. He was holding a 15-element yagi aimed at east San Jose foothills (location of K6BEN repeater), and he barely got in as can be seen here.

Nick could not talk on the radio and hold antenna at same time. He first fired this combination up 1/2 hour before our weekly Weds 8:30 pm video net. That's a cat that walked up to his leg. Later portion of this video file has a slightly better transmission during the Weds night net.

To access K6BEN amateur television station repeater, a 1255MHz FM video is the uplink, 421.25MHz regular AM NTSC video is downlink (compatible with consumer cable ready TV sets).

Wyman and Videolynx no longer sell 1.2GHz transmitters. One source are Mobicomm 1.2GHz ATV transmitters sold on ebay by seller ID "gnupic" which is based in Holland. These are only 50 to 80mWatt so a linear from DownEast Microwave or DEMI (http://downeastmicrowave.com). This linear amp (model 2330PATV) needs to be Class A specifically made for amateur TV, so verify before buying.

It appears the Mobicomm and DEMI combination puts out less than 1 watt. The Mobicomm may not have enough power to properly drive the DEMI linear. However, Mobicomm makes a 1 watt version of their 1.2GHz ATV transmitter. This latter combination remains to be tested. Reason for all this is to provide sources for newbies to get involved and do their own ATV transmissions. Nick said linear amp draws 3.5 amp on standby, only drew 5 amps when Mobicomm was on. I also tried my Mobicomm with a DEMI linear and I could not quite get an uplink, my Wyman at 1 watt barely got in.

This video file made without sound because I get Comcast interference at my home location on the VCR used to receive K6BEN on 421.25MHz which is same frequency as cable channel 57. Sound carrier was from the Comcast signal instead of K6BEN, however, K6BEN video carrier was strong enough to override (but not all that great).

Yes, Comcast is in violation of a leaky CATV system but I haven't put in the time to deal with it. Comcast customer service is the worst and FCC no longer enforces the airwaves.

Category:

Howto & Style

Tags:

• ATV
• amateur
• television
• N6QQQ
• K6BEN-ATV

[animobil]

Was anybody else waiting for Max Headroom to pop-out. But serously, ATV is awesome. I can't wait to get into it myself. I've had my license for two years now and i want to get into other stuff.

[nsayer]

That cat is named GIzmo. He's the star of the YouTube video "Gizmo Flushes."