26/04/2009
GB3TV now relayed
After a successful receive test earlier in the week; Dave G8ADM and Dave M0SAT visited the
repeater on Friday 24th April and removed the existing
23cm antenna used to receive GB3TV. A new 13cm
receive antenna was installed in its place and new
cables were fed through the roof and into the bell area
where a filter and downconverter are housed.
Due to a problem
with a connector the repeater was finally up and working
by 21:35 and a great interference free P5 digital
picture was received. Dave G8ADM also made some final
adjustments to the 70cm digital receiver and the new FEC
of 7/8 was set. Tz can now be selected by using the DTMF
control command BB2 (the old GB3TV link selector).
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P5 and no interference! |
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Good views to horizon 70cm |
"TZ is where?" |
Still on the phone! |
70cm Receive
The 70cm digital ATV input is now working properly.
Frequency: 436.00
Symbol Rate: 2.0 MS/s
FEC Ratio: 7/8
RF Bandwidth 2 MHz approx.
Antenna: Omni directional, Horizontal Polarization,
600ft ASL.
Sensing: Automatic, 2nd priority.
This 70cm receiver is overloaded and does not receive
any input if the GB3HR voice repeater is active.
This is due to the closeness of GB3HR to GB3BH, HR
overloads the BH receiver.
This can also be caused by nearby 70cm simplex contacts.
We have the best bandpass filter that we can get on the
input but the frequencies are just too close.
So far G8ASI and G8ADM have been received on 70cm.
30/12/2008
10GHz section back on air!
Dave G8ADM and Dave M0SAT visited the repeater on
Sunday 21st December to install the repaired and
upgraded 10GHz section of the repeater. A P5 report
from Anthony G7LRQ was immediately
reported to confirm that BH was back in action
again on 3cm. It is working well on
full power, 100W erp.
The problem was that the antenna tube broke and let the
weather in and a nearby lightning strike/flash damaged
the PA. The PA was repaired and a new bigger stronger
low loss tube fitted to protect the antenna.
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Extra reinforcing at base of new cover |
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Antenna cover before painting.
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The new tube was fixed to the
amplifier case using red glue inside, (which poured like
liquid) and gray glue outside. Flexible pipe was used
inside the base of the tube as an anchor... The new
outer tube was made using 120mm dia, 3mm thick acrylic.
The tube was offset from dead centre very slightly to
maintain a low VSWR.
Further good reports have since
been received from G6OUA (Luton), G7RZF (Croxley) &
G8ASP (Harpenden).
The video streaming via
www.batc.tv is also working now that we have wifi
free reception
via 10GHz.
01/12/2008
BH streaming live to the
internet on new BATC site
The BH video stream has been reinstated by Dave M0SAT
using 13cm receive. As 13cm is on low power it is
suffering from Wi-Fi interference. The stream has been
running successfully for the last week.
Using the free
streaming service,
www.BATC.TV,
viewers can experience BH "on-line" at over 200Kbps
which gives excellent quality. The new service uses
"Adobe Flash" streaming allowing most computers to
receive it. The delay is far better than the previous
Windows encoder versions with delays typically around
0.5 second, allowing QSO to take place even for those
who have no direct receive.
2 mtr audio
(144.750MHz) is now also being streamed but is currently
mixed at the encoder. This should be changed in the near
future to have a 2 channel audio stream (main video
audio on one channel and talkback on the other allowing
viewers to set their own "balance"). Please check back
here for updates to when this is implemented.
The main list page
of ATV repeaters being streamed via BATC.TV is
found
here
