[ARC5] US Submarine ELINT WWII, (was British ZB......?)

[Kenneth G. Gordon]

On 7 Apr 2021 at 15:11, Tim wrote:

> Hue said: But by US standards Japanese radars were rudimentary, not widely deployed, and also 
> ( without referring to my docs ) I believe mostly operated on lower frequency bands than US. It just 
> seems rather less likely or certainly, uncommon
> [snip]

Although SOME of their radars operated at around 3 gHz, most were lower frequencies, as I 
remember it.

I do remember reading a U.S. Army or Navy document concerning the installation of one their 
radars on some Japanese capital ship. It was remarked that a rather large bundle of wires 
were fed through a rather crude hole torched through at least one deck with no sort of 
grommeting to protect the wires from chafing. A very poor installation of an important bit of 
equipment.

> --------------------------------
> Generally true.....US Subs used the AN/APR-1 (and -4 presumably) hunting IJN ships/submarines 
> in the Pacific in WWII.  ..In researching the AN/APR-1 that I am playing with I learned that the 
> USS Batfish sank an IJN submarine after the APR-1 detected its 150 mc radar. Those IJN subs 
> also carried 3 Gc radars, at least late-war.  The APR-1 (SPR-1) could detect both radar band 
> emissions. I would expect many other intercepts were made with this gear.  It was a good passive 
> system and the APR-4 variant was used well into the Vietnam war era aboard EB-66 aircraft, 
> probably others.
> Some details if you're bored:  
> http://www.n6cc.com/an-apr-1-apr-4-radar-comm-surveillance-receiver/

Very interesting, Tim. Thank  you for writing that web page

I believe I own at least one of all of the tuning units used in the APR series of equipment. I 
have an APR-1, and I also own two of those very large and very heavy Scott-built Navy 
receivers which use those same tuning units, and I have, for the moment, forgotten their 
Navy "name", RDO?....or something. They weigh at least 100 lubs and have never been 
used. They are truly beautifully built. Once in a while, I slide one of them out of their cabinet 
simply to drool over the beautiful, beautiful construction.

I am tempted to ship at least one of them, at my cost, to anyone who really wants one.

I'll never use either of them and would hate to see them go to the dump when I kick.

I would suppose they belong on one of those museum ships...

Ken W7EKB