Fwd: Latest status on the KD4PBS ATV repeater
- I'm not sure this went out to everyone so I'm forwarding it to the group. Great progress Matt and the all the others helping!
Mark, WD4KSE---------- Forwarded message ----------
From: Matt Harris <kd4pbs1@...>
Date: Thu, Jul 29, 2010 at 8:41 PM
Subject: Latest status on the KD4PBS ATV repeater
Yo, Woody! Wazzup man?
Here's the latest status on the repeater...
This weekend, me, Sam (K4OC), Alex (KC4PHJ), Chris (KH2PM) and Byron (K4NGJ) moved the repeater to it's home at the Apex site.
We hooked up the TX feedline to the 420' antenna. Right now the RX feedline is not connected. The transmitter has no filter on it, but since we are using a professional exciter, it is making a good VSB signal for introducing to the antenna directly. Dave (WB4IUY) is currently working on the mechanical work for making the TX and RX filter. I will do the final tune using a network analyzer once it is made. We ended up with design for two 9-pole interdigital filters giving a bandwidth of 6 MHz centered on channel center for 421.25 and 434. These will be connected (probably) to the 1100' vertical antenna the 442.075 antenna is connected to. If we find issues with using this antenna, we will end up falling back to the current antenna at 420'. Currently the repeater is only giving us about 6 watts average power. I am hoping that Wayne can get up with me to let me know if and when I can go retrieve some of those 100W PAs from the translators that are living up in the mountains. I guess he is still on his sailboat out in the ocean somewhere right now? I sent him an email about a month ago but haven't heard from him.
The repeater is connected to the 442.075 repeater controllers second port. The ATV audio passes through this controller, so it gives us a wonderful linking opportunity. Currently one can go to 442.075 and enter some DTMF codes to link and unlink the ATV repeater. 28866 (it spells "ATVON" on a DTMF pad) will link the two repeaters' audio. 288633 unlinks them ("ATVOFF"). Please give these out to only members. Also, remember that the 442.075 repeater requires a 114.8Hz CTCSS tone most times.
The ATV repeater has a 15 second hang time. So, one can link the ATV repeater, and kerchunk 442.075. This will cause the ATV repeater to transmit for as long as one holds down the key on 442.075, and will give a 15 second "squelch tail" after unkeying their mic. This will let one see how well they can see the repeater. No worries on duty cycle; it's all pretty bulletproof. Also, they will hear themselves repeated from the 442.075 repeater out of the aural signal on the ATV repeater :) The video will be the test pattern that Sam sent you.
Hopefully Wayne will help get us a good PA for use on this machine.
All that is left is getting a good PA and getting the VSB interdigital filters made and tuned. I think I killed the PA trying to tune it down to 421.25. I hate to admit that I acatually had it putting out close to 100W at one time, but I guess I tweaked one too may times on it! LOL
Remember that this is VERTICAL polarized, so hopefully we won't interfere with the TV hill repeater in most areas.
We have come a LONG way with this project, and it is nice to have some high quality broadcast gear available for use with this.
I look forward to having the first QSO with y'all sometime SOON on this machine!!!!
To alcohol! The cause of, and solution to, all of life's problems!