Seavoice RT100
 

I recently bought another load of junk off eBay as my wife would say. It includes a marine band radio, a hand held direction finder and a sonar display.

The radio is a RT100. I think this is a vhf marine band radio. It will transmit into a test set but it’s dead on receive. It has separate crystal for transmit and receive 24 in total but I’m not certain if I’m even applying the correct frequency for receiving.

I think they can be setup for split frequency operating but not sure. I haven’t pulled any crystal yet for inspection but wondered if anyone had come across them before. It could be interesting try and convert it for 2m use.

Does anyone have any knowledge about the RT100.

Thanks Chris

Re: Seavoice RT100
 

It's a VHF FM transceiver. Channel 16 is the calling channel and it's simplex on 156.800MHz. It has the most used channels fitted unless someone's removed the crystals! Crystals these days are rather expensive now that synthesisers are so cheap!

You might be able to hear Humber Radio on channel 16 but I don't know what your local band plan is. It should all be on here.....

https://www.offshoreblue.com/comms/vhf-uk.php

Re: Seavoice RT100
 

Thanks for the information. I can hear a slight hiss but nothing more. I will try sweeping the frequency see if I can pick anything up.

Re: Seavoice RT100
 

Sorry entered my query in the wrong place

Regards

Bill

Re: Seavoice RT100
 

This radio was possibly made before the marine channel spacing was changed in the early 1970's and may not be suitable to use nowadays.
Mike

Re: Seavoice RT100
 

Electronic Laboratories (Seafarer) Poole was the company that developed out of Cyldon (Sydney S. Bird and Sons) after many many changes of name and direction. By the time this was made its unclear to me if anything of the original company was left.

I am asking a friend who did his apprenticeship there if he can shed light his Father was Chief designer there for many of the Seafarer and Seafix products.

Cheers

Mike T

Re: Seavoice RT100
 

I bought a box of various junk which is proving entertaining. The DF gun with its large ferrite rod and liquid filled compass is very interesting. I think the LF beacon were superseded by GPS many years ago. It does tune into radio 4 long wave which is kind of fun.

Regards the transmitter I am aware of licensing conditions. I think it does use the old channel spacing

Re: Seavoice RT100
 

You should still be able to find some beacons on the Seafix. The marine ones have gone but some aeronautical beacons are still active.
And it's quite a collector's item, especially as it still has the compass.

Re: Seavoice RT100
 

Just now I had a quick look at the NDB band, at least a dozen or so showing well on the waterfall (software defined radio display). All you need to do is get the bearing of a few and then you can find where you are. A shade redundant but I do think a worthwhile exercise to find out how accurate such things are. I tried a while age using my loop aerial and rotator, got to two miles of reality. Mind you I have a few close NDBs (aeronautical Non Directional Beacons) one is only three miles away.

Re: Seavoice RT100
 

I will have to have a twiddle see if I can hear anything apart from radio 4 !

Re: Seavoice RT100
 

Hi
I worked at Seafarer in 1976 when the RT100 was being made at about 100/week
Yes, it can be tuned to 2m- crystals permitting...and several were.
Coincidentally, I gave away my copy of the service and user manuals 2 weeks ago. I expect that I could borrow them

it's ok for the current channels and, AFAIR, had 1 or 2 split channels for link calls.

good luck

John g8jmb

Re: Seavoice RT100
 

You have a selection of the most commonly used channels on the old band plan-
Channel 6 - 156.300 simplex - intership secondary
Channel 8 - 156.400 simplex - intership primary
Channel 12 - 156.600 simplex - Port operations
Channel 14 - 156.700 simplex - Port operations
Channel 16 - 156.800 simplex - Distress, safety, calling
All the high number channels are duplex port operations.

Don't know where you are in South Yorkshire, you might get some traffic on Ch16 from the Humber Radio coast station if they're still in operation (it's 55 years since I was up and down that coast!) and there might some activity around Whitby.

Re: Seavoice RT100
 

GKZ Humber Radio closed down in June 2000......


http://coastradio.intco.biz/uk/gkz/index.htm

Re: Seavoice RT100
 

Thanks for the channel information that’s really useful. I thought it could have been split as I don’t have anything’s on receive when fed with a signal generator. I have another radio on the bench right now, but I will pull some of the Crystals and check the frequency if I can identify the receiver IF.

Re: Seavoice RT100
 

You'll need a receiver crystal for Marine Channel 67 to listen to HM Coastguard weather, navigation warnings, etc. I think that Humber Coastguard covers most of the southern North Sea.

Cheers

Roger