Upgrading Nasa Clipper speed and depth with Airmar B744v ?

[sarabande]

ATM I have the NASA kit for depth and speed, installed in two separate units towards the sharp end.

I have read that the plastic of the housing and the impeller can be vulnerable to damage from impact, especially if the unit has been installed for several years.

I also have, from my previous boat, an unused Airmar 744V triducer,

b744v.pdf (airmar.com)

which is entirely beefier item, and also has water temperature which could be useful for fog anticipation . There are a number of instrument faces which use the Airmar data and which could be bought to replace the NASA dials.


Yes, there's a bit of gadgetophily about having a new piece of kit, but it would be handy to hear from anyone who has the Airmar B744v installed, so see how it works in practice, please.



Or do I flog it and buy new NASA depth and speed with the proceeds ?

 

[MikeCC]

If the NASA is working and you're happy with it, you could just bed in the skin fitting with filler to reduce any doubts about breakage. Be sure to abrade/clean GRP beforehand.

If you want to replace it, might be better selling the B744 and getting a flush face transducer.

 

[Ian_Edwards]

As far as I can see from the spec's the NASA transducer is tuned to 150kHz, the Airmar B744v is a 50/200kHz transducer.

I don't think that it will work effectively, the B744v 200kHz centre frequency is too far away from the 150kHz.

It won't be well matched to either the NASA transmitter or receiver.

 

[Wing Mark]

If the issue is really the plastic skin fitting, maybe you could just replace that every few years?
If the issue is that it's vulnerable to damage from inside your boat, your could add something to protect it.

I have Nasa log and depth. The depth is interna;, the log paddle wheel is in front of a bulkhead, and a floor has bee glassed in ahead of it, so it's unlikely to get knocked.
It might be possible to make/modify/buy a metal skin fitting?

While my boat was out being surveyed, I did give the skin fitting a bit of a clout to test it, I think it's pretty tough.