Boat Radar

[KL7OF]

It is a Furuno...Made in Japan....Has a CRT.....Obsolete in todays world of Garmin mini radar/gps plotters...It had the 17 conductor cord plus coax  cut when it was removed from a fishing boat.. I spliced it all back together and it works FB... 4 distance scales from 2 to 16 mile range....each scale divided into 4 segments....  I can run it here without fear of interfering with anything important as I am in the middle of a boat yard and across the road from about 60 fishing boats anchored up in the river.....They all have the radar on......Fun to play with....The antenna , a printed circuit board, has some corrosion in the upper corner from a steel screw but it doesn't seem to effect operation...I can't find any owner manual or schematic on the web for this particular unit.....
  What would be the best way to clean that antenna PC board?....Pencil eraser?
   I would like to put this on a mast on top of my building to see what I can pick up....It has  a 30 ft connection cord...could be fun..

[KL7OF]

closer view

[Opcom]

It has been operated wet, likely, try any product designed to stop corrosion on copper, wash with pure water inn case there has been salt. Possibly remove the pcb to clean.. definitely clean around that screw. Possibly use fine stel wool, so gently with solvent and detergent mix. Best to clean down to bare copper if possible. And esp. Clean scrub around that hole to eliminate residue. The volts can actually be quite higk peaks, low curent, treat accordingly. Do not coat, axcept maybe clear if necesary.
Sorry about spelling, I am learning a tablet. I have fixed radars before. I love them.

[WA3VJB]

Yeah that should be fun to set up and watch.  

MCM Electronics and others have these little burnishing pens that have a bundle of cut fiberglass strands on the end, and a push button extender just like a pen as you wear them down.  

http://www.mcmelectronics.com/product/SABU10191

They're cleaner than a pencil eraser (more abrasive however, so a lighter touch needed) and if you get one you will wonder how you did without.  I especially like an alternative to the use of solvents or cleansing chemicals when there are components nearby.

I was offered a unit similar to yours that had come off a rather large cabin cruiser that was being refitted.  This was before smartphones and weather apps, and I considered grabbing it because we could "check the weather" with this at home before we'd set off in the boat. 

It was a fully functional, but elderly radar. Never got around to acquiring it and I'm sure it ended up in a dumpster. They remain very expensive, what a waste.

[WD8KDG]

Great to see if NSA has a drone overhead

Craig,

[Opcom]

Great to see if NSA has a drone overhead

Craig,

To see but not track, alas the really good radars are as well

[WD8KDG]

Steve,

Be sure to bring that item back to Tum Tum. You can be the official souce of "Big Brother is watching reports" in the PNW.

Craig,

[Steve - K4HX]

Could this be considered a boatanchor radar?

[Opcom]

It's not heavy enough to be a BA. It has at least two tubes, a magnetron and a TR tube, but the RX may be solid state instead of a klystron, by the looks of it. The really new ones do an FM CW emission at low average power and use DSP.

A boat anchor radar (IMHO) need not be all tube, but ought to be at least from the 1970's, so as to have no CPU but a few boards full of DIP ICs, a large power supply generally separate from the display, likely have the TX, pulse forming network, and converter/IF all mounted on a rotating platform served by slip rings, and have an analog PPI display with a round tube, not a raster scan rectangular type coming from a video generator IC. It ought to have dangerous voltages all over the insides as well. big heavy stuff, a 4 FT diameter radome, 80 lbs, plus the other pieces.. Aircraft nose-radar navigational units are much lighter but don't do a 360 degree scan.

as long as the topic is so fresh, there are many good books for radar enthusiasts, esp. those who like what's inside the radar, not just that's on the display or what the knobs or buttons look like.

These go beyond the many low-tech volumes designed to generally explain radar to intermediate users, entry level repair personnel, and shipmasters. Those are fine to start with, but at some point they leave many questions unanswered.

Between those volumes and the ones below lies the realm of the FCC "ship radar endorsement" on the radiotelephone license. There are some books for that, the usual study guides.

The ones below, you can really get your teeth into:

MIT Radiation Laboratory series, 28 volumes. (quite old, but there are 28 volumes..)

1st and 2nd editions of the "RADAR Handbook" by Skolnik.

"Radar principles, technology, applications"  by Edde.

"Principles of modern radar" - Eaves and Reedy (editors).

"Principles of radar" -MIT radar school.

"Radar Design principles" by Nathan.

Each has its own merits and technology generations, no single volume covers every aspect or use of radar, and this list does not cover every application. Radar has become an extremely complex and engaging topic as so many functions (features) have been added throughout the decades.

have fun! find them used on Amazon!!

weighty tomes are light reading for those who find little substance in light topics.

[KL7OF]

The Magnetron is mounted on the antenna unit and kind of swims around on its base....It is held in place but can move about 1/8 inch in any direction.....Seems to be built that way...

[Opcom]

That one has one of those rotating microwave joints, odd that the mag would be loose, they are usually solidly mounted to the waveguide. Are you sure the tube itself is loose or maybe the magnet or the T/R housing?

While you are working on it, if you can tilt the antenna up about 15-20 degrees, it'll do better for weather and UFOs, and not see as much ground clutter. There is also a jumper or test point somewhere to check magnetron current using a scope to see the current pulse without getting into the high voltage. This is a way to indirectly check the magnetron as when they get weak the current drops away. Have you found the manual on line anywhere? It would be interesting to look at the schematic. Raytheon put a bunch of their older ones online.

I hope I am not assuming too much, you likely know how to work on these things as well, for me their study is also a hobby and I'm enthusiastic about it. There is no discussion board for radar tech. that I know of. Boating ones don't count. That's like a home theater user group comparing TV sets.

The BA 'standard' I was suggesting, it was only a suggestion or opinion, was to where that whole radome electronics package there would be in a box behind the antenna and spin, with slip rings for each supply voltage  and various timing and video/return signals. I had an old Raytheon Pathfinder like that. Wasn't much plastic in there. The ant. was a horn fed by a row of staggered slots and was about 1M long and 8-9" deep making the radome more like 48" diameter. To be fair it was a higher power unit, maybe 15KW, and had a 72 mile range, but it was very inefficient and took 12V@40A. Its CRT was round and had a motor driven rotating coil with slip rings. The ant. position pulse would sync up the CRT coil rotation, all analog servos, the spec was something like 2 seconds to do so after being taken from standby to operate. It had a synchronous motor on each end, the radome driven by a worm on a big motor, and CRT a small motor with some gears. I sort of miss it now because of all the front panel user controls and cool analog circuits.

Please post pics of the repair and also some screen shots when you get it going. Where you are there would not be anyone questioning its use. I'm not so fortunate, being in the city, it might cause tracks on airborne navigation radars. It should not, because the frequency is supposed to be different but who knows what's being flown. The old Raytheon Pathfinder, intended for boats, had the radome modded to hang inverted under a chopper (re-arrange thrust bearings) and was used that way for years according to the gent who sold it to me for $75. What a PITA it was to disassemble that and restore to original.

I'd like an S-band which is better for sensing raindrop size and hail if anyone has one reasonable. not fussy but 360 deg. PPI capability is preferred to sector scanners.

[Tom WA3KLR]

...it might cause tracks on airborne navigation radars.

An engineer I worked with once said that this interference was called "pecker tracks".

[N0WEK]

Sort of tangentially, does anyone lust after a Narco/Konel Loran A unit?

It was a "portable" aircraft unit that the aircraft ferry company I used to fly for bought. It never really did the job and it was a bear to teach the pilots to use it with the special charts.

It hangs from what looks like a giant CB under dash mount and is about 16 x 12 x 6 inches. It has a 3 inch CRT but the rest is solid state from about 1970 or so.

There are no Loran A chains left after the mid 80s (Loran C is hanging on in Alaska).

It'd make a great museum piece or project, I'm just looking to find it a good home.

I'm on the road at the moment, but I did find this picture from a 1970 ad for sale on Ebay.

[K3ZS]

Where I used to work, we had an X-band radar made for aircraft.  It was a sector scanner, but it was mounted with a TV antenna rotator so it could be used as a ground based weather radar and aimed in the direction of approaching storms.