Hi Dan,

Thanks for your email - lots of stuff I haven't thought about, well done.

The complexity of injecting canned TS (test card, ID etc) when there isn't valid TS from the RX should not be difficult, there is also the regulatory requirement for repeater ID to be thought about. I do like the idea of using CW tone in the audio channel for repeater ident - it has a certain ridiculous ring to it :)

Certainly plenty to think about - suddenly you have a data repeater, which incidentally carries video and audio.

Would you mind if I published this email from the web site (including you call sign, but less email address) ? This is exactly the sort of conversation that I hoped for when I published the page.

Regards,

Mark



From: Daniel Cussen <dan@xxxxx.com>
Subject: DigiLite-ZL - Transparent pipe repeater
To: markaren10@yahoo.com
Received: Friday, 16 September, 2011, 5:23 AM

Hi Mark,

I have read your hard work done on DigiLite-ZL. It seems to be a great idea and very progressed already.

I will follow your progress keenly. I am involved in a TV repeater in Ireland and I have been investigating a digital transmit option for the past 6 months.

One idea I came upon was using a DVB-S to transport stream receiver connected directly to a DVB-S transport stream transmitter. Basically whatever is received is re-transmitted without much processing. This idea should work with MPEG-2 and MPEG-4 and also with multiple audio streams, teletext, data etc. without the need for a PC and complex
processing at the repeater site.

So there would be no analogue input, no MPEG encoding decoding etc.

The only problem I see is that when there is no input the repeater will output nothing. 2 potential solutions are a low power transmitter with a test card transmitting into the repeater 24/7 from a nearby ham. When the repeater is to be used this could be turned off with a DTMF tone. Another, more complicated idea, is to detect if a valid transport stream is coming out of the receiver and if not then create a transport stream with a test card.

I have researched S-R systems setup. In particular I am interested in their combined Data (high speed packet) and video combined on the one stream with a return path.

The have DVB-S receivers to transport stream and they have transport stream to DVB-S modulators. In theory you just need to connect one to the other and you have a full functional "dumb" repeater, that will work for MPEG2/4 video, data, audio etc, etc etc.

Here is the DVB-S receiver http://sr-systems.de/content.php?show=NIM-DVB-S&lng=eng&style=std

and here is the DVB-S modulator http://sr-systems.de/content.php?show=DVB-MiniMod3&lng=eng&style=std

The ethernet bridge (2 way ethernet over DVB stream) guide is here: http://sr-systems.de/content.php?show=Downloads&style=std&lng=eng&action=download&alias=MiniMux_ETH-Bridge_Guide

Which gave me the idea for a "dumb" repeater.

I don't know all the in's and outs of how to do all this but, you might know and you might consider this as a feature if you think it warrants it.

Thanks for all your work so far and thanks in advance for all your future work!

73s

Dan EI9FHB