Signet depth transponder?

Lazy1

.
Aug 23, 2019
173
Catalina 22 13425 A driveway in Pittsburgh
Hi,
Question about old depth sounder and transponder. If you take a look at this youtube Video I took by shoving a gopro up my ol' sole hole you can see my depth transponder that was installed by the original owner (OO) I am guessing.
The depth finder and knotlog each their own transponder and after watching a couple videos of sailors having their thru-hulls punched by choppy seas I thought I should get an understanding of what I have. The knotlog has a paddle wheel transponder albeit broken, under the dinette seat and easily accessible. The depth transponder is in a place where I cannot access and wonder how it was installed. I see no evidence that it is a thru-hull from the exterior, maybe the contraption surrounding the transponder is a in-hull adapter?
The stuff is all Signet and from what I can find it all dates to when the boat was new in 1986.
My question is if anyone would know if these transponders are likely to fail, I think I can reuse it if I find another depth sounder that uses a 200khz transponder. I am not sure yet that I dont have a bad wire because the depth finder reads 18.8 which is coincidentally what the newer models read when I see them on ebay (default no signal read out?)
The transponder wire is labeled mk272.88 - 200khz with a RCA plug. Will a continuity check show anything?

I would like to have a depth finder but do not want a transom mount or drill a thru-hull, especially if I might have something already there. I think it was stingy sailor who has a thing on converting RCA to two-wire for newer units.
 
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dmax

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Jul 29, 2018
970
O'Day 35 Buzzards Bay
I had Signet instruments on a previous boat - the depth sounder was always flaky (would read 0.0 at the worst times). Sent it back to the factory to be "fixed" - no change. Similar issues with speed and wind instruments - they were junk, and that's when they weren't very old. I would rip out the knot meter and get a GPS/Fish Finder combo with a through hull that fits in the hole (2 1/8" if I remember correctly, I was able to replace it with a 2"", never leaked). That knot meter through hull could fail and sink your boat as well.
 
May 23, 2016
1,024
Catalina 22 #12502 BSC
glass in the thru hull, get a $300-500 depth/chartplotter and stick the transponder in a wad of plumbers putty in the bow and be done...
 
Apr 11, 2017
571
Catalina C22 Solomon's Island, MD
The plumber's putty is by far the easiest option - I've done it on several boats, and it works great. If the readings are a little flakey, it's an easy matter to relocate it to a different place in the hull. Basic depth finders are really cheap now-a-days-
 
Sep 30, 2013
3,538
1988 Catalina 22 North Florida
I recently helped a friend sail his new-to-him Cal 33 back home from south Florida. Along the way, the depth readings went out while the boat was pounding pretty hard ... turns out the PO had the transducer bedded in a big mound of VASELINE. :laugh:
 

Lazy1

.
Aug 23, 2019
173
Catalina 22 13425 A driveway in Pittsburgh
I recently helped a friend sail his new-to-him Cal 33 back home from south Florida. Along the way, the depth readings went out while the boat was pounding pretty hard ... turns out the PO had the transducer bedded in a big mound of VASELINE. :laugh:
Who dosn't keep a big tub of vaseline onboard? :redface:
 

Lazy1

.
Aug 23, 2019
173
Catalina 22 13425 A driveway in Pittsburgh
Does anyone know how to get to that area on a MKII? It seems like a great place for the transponder but all of the holds are molded in in that area from what I can tell. Unless there is a opening under the porta-potty which I have never moved.
 

Lazy1

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Aug 23, 2019
173
Catalina 22 13425 A driveway in Pittsburgh
So moving on and suffering from feature creep...
I think I am going to get one of the Garmin 4 series fishfinders to get depth and thought Clearvue option looked pretty cool for less than a $100 more and then looked at the Echomap 43cv at $299.
Where do I stop obsessing?
 
Apr 11, 2017
571
Catalina C22 Solomon's Island, MD
I think any of even the basic models would work well enough for the needs of a C22. I'd check the reviews to make the screen display is bright enough though - being washed out from the sunshine is about the only real problems I've had.