NEHA

I don't know about "down right irresponsible".
Trying to be constructive.
Would it be possible to use two sets of "HTs"? One just to listen?
John

Two channels can create either 2 party duplex (listen on one talk on the other) or an emergency monitor channel.

Off the top of my head, here are an issue or 2 with either.

2 channel used as duplex.
- Radio reception is still not multi-party. Only the strongest transmission is locked onto by the receiver. That is further complicated by the weaker transmission garbling the stronger in many receivers rendering both messages unintelligible.

second emergency only channel.
- Ensuring the radios are always working and in range. The only way short of regularly talking and hearing something on this channel is to make up some smart system that requires every radio check in every few seconds and generate a warning to both control and the radio holder if the check-in fails. This is not an issue with simple duplex systems like the party line telephone we use now because everyone can hear everyone elses transmissions all the time and you know within a few seconds if something has gone wrong anywhere.

And with both.

Protocol and discipline are much more important because anyone holding down a PTT button will "own" or at least render useless a channel to anyone else. I listen to people who claim to be well schooled in both (ham radio operators) at rallies effectively lock up communications pretty regularly. If these folks cant do it right all the time, what chance do our folks have with less training, a more complex system and one that is arguably more critical to event safety to boot?

walterclark wrote:Radio reception is still not multi-party. Only the strongest transmission is locked onto by the receiver. That is further complicated by the weaker transmission garbling the stronger in many receivers rendering both messages unintelligible.

Thanks for verifying that. That in fact is what seemed to happen. Some of the hill heard the person calling in the car that was off. Some heard heard Drew. This just made things more confusing since after two calls that a car was off, half the hill still didn't have a clue that anything was wrong.

I forgot one other thing associated with having 2 similar (same band - relatively close in frequency) radios in close physical proximity... The one transmitting can overwhelm RF the front end or the IF (mostly a mixer and filters, a characteristic of hetrodyne radios) of the one in receive so that even though they are not on the same frequency, the receiver will not be able to detect transmissions on its channel. It is less of an issue with relatively low power transmissions like that of HT's but if a single person is holding both of them it may well become one.

If there is a way to do it, I think the panic tone method would be best-there would no mistaking of someone pushing the wrong button to call in -and talking on the wrong frequency-and as far as testing the system-that can easily be checked like they do on a normal basis. At the start of every run group-and after there has been any delay, control always does a course check. It could simply be changed to 'Ok-give me a radio + panic tone test starting with check#7". "Check 7 here--beeep"

Questions for whoever is doing this. Is it going to be used for Ascutney 1? If so, have provisions for use of the start light/timing system been made as well?

How long do the base station batteries last with frequent transmission? Last time we tried this, IIRC, it was less than a day.

So...how did the test go?

I believe we will get something from the team. I was just a helper. I was impressed with the coverage. There are still some issues. The Spring Ascutney will be run with wire.
John Marsha
this was sent fron my iPud3

Mopar 151 wrote:How long do the base station batteries last with frequent transmission? Last time we tried this, IIRC, it was less than a day.

Which base stations are you referring to? There were 3 or 4 older radio units mounted to planks of wood in the trailer. We ended up trying one of them because a fuse blew in one of the radios we were testing.