Difference between revisions of "51 MHz"

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51 MHz DATV
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==51 MHz DATV Introduction==
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from [https://forum.batc.org.uk/viewtopic.php?f=15&t=7847 50 MHz - a reminder - Forum post ]
 
from [https://forum.batc.org.uk/viewtopic.php?f=15&t=7847 50 MHz - a reminder - Forum post ]
  
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The Mini-Circuits RBP-75 band pass filter will pass 51.7MHz. Other low power filters are to be found on the QRP-Labs shop pages for under £5 each
 
The Mini-Circuits RBP-75 band pass filter will pass 51.7MHz. Other low power filters are to be found on the QRP-Labs shop pages for under £5 each
  
In the [[70MHz_filters|70MHz Filters section of this Wiki]] G4GUO's low pass filter from CQ-TV-260 intended for 71MHz duty will do also well for 51.7MHz.
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In the [[70MHz_filters|70MHz Filters section of this Wiki]] G4GUO's low pass filter from CQ-TV-260 intended for 71MHz duty will do also well for 51.7MHz. Note flat top response 50 Hz [spike on left of spectrum] to 75 MHz
  
 
A cheap, lightweight antenna for your initial tests is [https://sites.google.com/site/gw7aav2/50mhzdeltaloop Steve GW&AAV's delta loop] Also a combined pair of these antennas are shown on his 4m page.
 
A cheap, lightweight antenna for your initial tests is [https://sites.google.com/site/gw7aav2/50mhzdeltaloop Steve GW&AAV's delta loop] Also a combined pair of these antennas are shown on his 4m page.

Latest revision as of 18:33, 24 February 2023

51 MHz DATV Introduction

from 50 MHz - a reminder - Forum post

The bandplan recommends 51.7 MHz. Probably best to start with 333 kHz DVB-T, QPSK, Guard 1/32, FEC 2/3.

For receive, you can tune there directly with a Knucker tuner and a Portsdown or Ryde. I would suggest a band-pass filter and a preamp (in that order).

For transmit, you can use a Portsdown 4 with LimeSDR, which will give you +1 dBm on 51.7 Mhz with a Lime Gain of 92. Or you can use a Portsdown 4 with a Pluto, which will give you -10 dBm at 0 Pluto Power (the maximum).

Dave, G8GKQ

Receive upconverter detailed on 71_MHz Wiki page will also make a 451.7 MHz signal if DVB-S or S2 is being fed into a Minitiouner.

The Mini-Circuits RBP-75 band pass filter will pass 51.7MHz. Other low power filters are to be found on the QRP-Labs shop pages for under £5 each

In the 70MHz Filters section of this Wiki G4GUO's low pass filter from CQ-TV-260 intended for 71MHz duty will do also well for 51.7MHz. Note flat top response 50 Hz [spike on left of spectrum] to 75 MHz

A cheap, lightweight antenna for your initial tests is Steve GW&AAV's delta loop Also a combined pair of these antennas are shown on his 4m page.