Clansman 352 question

[tinweasle]

Probably a daft question but the Clansman 352 can be used as a longer range manpack, I would assume this was done in rural area's where you would be further away from help. Now I know that the normal 351 antenna's could not take the extra power so a GSA was carried. Now my question is, as the GSA takes time to set up and needs to be driven into the ground to use the 352 cant be used while moving, so would the amp have been disconected and a whip antenna fitted for when you were moving so you can at least get incoming messages and set up when needed, was there another way around this or was the 352 not often used on foot patrol?

 

Cheers

 

Shaun

[johnhughes]

You simply switch off the AMP remove your GSA and add the whip. you don't need to play with the wiring or physically remove the AMP from the radio assembly

 

 

j

[tinweasle]

Doh I have looked at my set up for over an hour and had not noticed the off switch on the amp :red::red::red:

 

Cheers

 

Shaun

[5645andym]

You simply switch off the AMP remove your GSA and add the whip. you don't need to play with the wiring or physically remove the AMP from the radio assembly

 

 

j

 

I was told that the reason the GSA was used with the 20 watt amp was not that the 1.2 m rod antenna on the 351 could not take the power but because there was a risk of radiation burns to the operator if the rod whipped around and touched his neck or head while on transmit.

 

Mind you I also heard that the output from the amp could be run through a length of co-ax cable via (an already tuned) 4 watt SURF unit to the rod IF you really really had to use 20 watts while on the move . . . I never tried it but always wondered if it worked or if it burnt the SURF out?

[g0ozs]

Andy

 

I have also been told by someone who used the set in service that it was possible to use the 20W amp with the whip antenna by using a pre-tuned SURF. The SURF is really a co siting band pass filter rather than an antenna tuner but it at least provides the transition from BNC coax to whip base required. It needs to be pre tuned at low power because it will otherwise block/absorb the output if off frequency and something is going to get hot! (bearing in mind it is a 4w SURF and a 20W amp!)

 

It's also worth noting that the 20w amp is actually likely to give a lot more than 20w on a decent or float charged battery - of the dozen or so I tested and sold on e-Bay in 2010 all were good for at least 25w on 1 band and some managed up to 28w!

 

The GSA (or a TUAAM/ARFAT combination connected to the 352 via an initiate box) would be a better choice because the antenna is properly tuned - by using the right number of elements in the GSA or by the TUAAM acting as an antenna tuning unit) whereas the whips are a compromise that are only efficient on the frequency where they are 1/4 wave long. Since inefficient antennas reflect power they can't radiate back to the source the 20w amp will likely get hot sooner if nothing else when using an unmatched whip!

 

I've also used the 352 with an EVHF pineapple quite happily although I wonder if the extra height of an 8 or 11m mast compensates for the inherent loss in the matching network inside the pineapple base - on all my test gear they show as way worse matched than a GSA set to the right length. I suspect that the elevated GSA with 20w is actually the most efficient of the lot at getting power radiated !

 

Regards

 

Iain