The AM Forum

Have a chance to get either one.  Had a 390-A, but never a 390.  Your thoughts on performance, etc.???

Why not both???

Jay,
Why get that old junk when you have a flex?

Brett
(very smug)

if you had a 390A before why not try a 390?

Hi Jay,

I have them both. I have a 1953 Motorola R-390 and a 1967 EAC R-390A. They are completely operational, and installed within my shack. In fact, I was listening to 160M last night on the R-390.

I really like these receivers, and I take the audio off of the diode load in either of them and feed it into a high quality outboard tube amplifier and speaker arrangement. The internal line or local audio section in either receiver is for the birds in my opinion; poor quality telephone-grade audio transformers with very little usable response much below 150 hz, and high-distortion pentode voltage amplifiers. Once you take the audio off the diode load and use an outboard amplfier, the quality improves radically. Neither receiver was designed for hi-fidelity reproduction; they were designed for use in RTTY, radiotelegraphy, and communications-grade AM circuits.

To some extent,  I think the R-390A gets something of a bad rap for poorer audio quality due to the ringing inherent in the magnetostrictive filters in the IF section. Again, when the audio is sampled off of the diode load, the audio quality is much improved, although the ringing remains somewhat apparent. I would not consider it highly irritating, however.

The R-390 on the other hand, employs an L-C filter arrangement in the IF. The audio is much smoother due to the relative freedom from ringing within the IF strip. I can listen to AM broadcast stations or high quality amateur AM signals for hours on end with my R-390 with very little listening fatigue; as I stated above, I do notice some ringing artifacts in the audio with the R-390A. One thing I have always noticed about the R-390; strange as it may seem, the lowest octave of bass is much more prominent with the R-390 when the audio is taken off of the diode load, compared to the R-390A. For example, when a strong carrier comes on the air, it can really move the 15-inch woofer in my speaker cabinet, whereas I really do not notice this same effect as prominently with the R-390A. I am using DC coupling off of the detector in both receivers; I think the suggestion some users have made about utilizing a 10 uf DC blocking capacitor is not valid, as there should be no DC component at the detector output, and the cap is superfluous in this case.

As I said earlier, I really like them both and my R-390 and R-390A are keepers. I could honestly live with either of them for high-quality/high-fidelity AM receiving usage, but my ultimate choice would be to go for an R-390. They are somewhat more difficult to source, but it is still a very common receiver, relatively speaking.

Prices for both receivers have dropped markedly in recent years, but the R-390 still commands something of a premium, probably for the reasons I have provided.

I hope that this helps. As with anything else, your needs and mileage may vary.

73,

Bruce

Jay
They are both great receivers. Heavy and will not break. And if cared for will last longer than us.
THey may not shine in tight busy bands and they are not a contest radio, but great A.M. radios.
They were designed to be in a hot comm center and tuned to whatever freq was being transmitted and be a reliable unbreakable radio.

Fred

I prefer the 390 myself.  A little better audio, and more substantial engineering.  BUT - remember the 390 is a lot rarer than the 390A and parts harder to obtain.  About the only components in common are the knobs and the Veeder-Root counter  ;D

The 390 uses a completely different power supply design - the whole B+ is regulated by a pair of 6082 dual triodes, which are mounted upside down and spread their prodigious heat upwards to their sockets.  One 390 I had, the bases on the 6082s were literally charred from heat.  The 6082 is rather uncommon, and not too expensive, but it can be replaced with a TV horizontal output transistor if need be.

If the R-390 you're after is in primo shape and all other things being equal, I'd suggest that one.  If either are gonna need work,  go for the 390A.  Or, as Buddly suggested, go fer both!

The both suck. They are heavy, use tons of power, and have lots of tubes. Neither has a digital read out, spectrum display, variable filters, sync detection and recording capability. The pieces of crap don't even have a USB or Firewire connector on them!

But they were built to defeat Communism. Get one.

     Defeating Communism sounds good to me! Where can I buy one? 73s, Marty, KK4RF

I have an R-390A. It's the shack work-horse.  I use mine for everything, including music on the BC band to 75M AM "Battle Conditions" receiving. I just feed the audio out through a transformer into a 12 inch speaker.  Sounds find to me.  Band changes are a bit tough, you don't want to go from 160 to 10 meters a lot.

It's a very good receiver.

Get neither and find a R-725A and have the best of both worlds. It is basically a 390A with a 390 IF module and was used for data and diversity reception since the mechanical filter phase delay made it impossible. You can also clone your own.

I wouldnt let a 390 in the house having worked on them and the 390A in the Navy. It is a mechanical Rube Goldberg and its unreliability is why the 390A was developed.

All versions need audio and AGC help for ham use as well as a product detector for SSB/CW. Ive heard that the Sherwood SE3 works wonders on them for AM. I have a Hammarlund HC-1 on a 390A but it gets little use these days.

Carl
KM1H

R390A followed at the I.F. output by an R1307A so there is your variable IF with 1-2-4-8 KC bandwidth, USB, LSB, CW/BFO, FM, and FSK, plus an audio bandwidth selection of flat-6KC-2KC,  along with very good audio from PP triode connected 6AQ5's and an oversized OPT and if that is not good enough for golden ears take the audio from the volume control.

take that ya smug flex owners!!

According to the military, the 390A was developed primarily as a cost reduction measure, not to improve performance.  I even have a TM that describes the differences and how each of the major changes reduced costs. The mechanical filters offer slightly sharper selectivity, at the expense of the filter ringing distortion.

Another good receiver is the R-392.  It is a compact version of the R-390, with tubes running off 28v for both plate and filament.  It has better audio with a push-pull final stage.  There is no 16 kc/s selectivity option, but the 2-4-8 are about the same as the 390.

Actually, the selectivity available with the 390A sucks.  The 4 kc/s is too narrow for AM  except under extremely crowded condx, but 8 kc/s is too wide for typical prime time ham band congestion. They really needed to have included a 6 kc/s filter in addition to the 4 and 8.

I have found the 390 and 392 to work better in the 4k position since the skirts are not quite so tight.

The biggest problem I have found with these receivers is lack of maintenance of the mechanical assemblies.  In particular, the roller bearings that ride the edges of the cams may freeze up from lack of oil, so that the roller slides along the cam instead of rolling, and this wears a dimple into the  roller.  Once that happens, it is nearly impossible to  get it to roll again, no matter how much cleaning and lubricating is done. It will stop as soon as the dimple contacts the cam, and just slide along, of course wearing an even deeper dimple into the surface.  I have managed to file out the dimple in a couple of cases enough to get it to roll again, but the wear had not become excessive; still, I don't think it would ever work as reliably as an undamaged one.

Use light machine oil on the roller bearing, and grease on the surface of the cam edges.

I also have both, very fine examples that were completely rebuilt by Rick Mish.  If I had to part with one, I'd let the 390A go before the 390.  The 390 with a Sherwood sync detector gets the most use.

Some time ago, one of the 6082 regulators tubes went south.  I purchased several spares,  and also tried a commercially available solid state regulator module.  The regulator kit didn't work properly, and I pulled it out and put the 6082s back in. 

Grant/NQ5T

I don't think Jay is a guy who likes to work on radios.
If you break a clamp, that can be a lot of work to fix.

I did really like the IF output on the r390, it seemed to work very well on transmit with no signs of overloading, the level was close to the receive level which made the o scope a handy monitor of RX and TX signals.

My R390a seemed a bit on the noisy side, and I could copy weak signals much better on the homebrew.

Its big and heavy, but its likely the best of the old tube receivers overall...

Brett

That is only part of the picture. Cost reduction included maintenance and spares costs also.

Collins built what they were told in the bid description and contract. The Army was behind the criteria and it was a circle jerk design by committee from the start. Granted the concept was fine and the end result met the goals when it left the factory. The 390 is still a fine radio if you have the skills to restore one or simply write checks to someone else. I just wouldnt want one as my main radio considering the potential down time involved.

OTOH, aging mechanical filters and the work involved to overhaul them to eliminate most of the ringing is a valid concern for the 390A. Perhaps there are other filters that could be adapted from the S Line or elsewhere?

Carl
KM1H

Therein lies the real story. Once you've played with them for a while it's not an issue, provided you have the required tools and some basic sense. Though I do get a chuckle out of the new-age 'experts' who claim to have restored theirs, when they actually had the panel painted and sent the radio to Mish and/or Ripple. Find users who have used and repaired them for a decade or more for accurate info if you really need precise info.

I do know of a few 725s that will be coming available in the next year, but they won't be cheap. Like Johnny, I prefer the original R-390 myself. For you Jay, unless you want to pluck the audio off the diode load as with the A model, the R-390 is a decent radio once it's returned to top form. Just make sure it's where you want it when you set it down. ;)


If you have the bulkhead adaptor from the dead filter or a replacement, you can use any number of options. The Dave Curry filters are nice but again, not cheap. IIRC, the 9kc filter is actually ceramic, not mechanical. The common failure of the old filters appears to be melted foam rubber used to support and isolate the filter from the case. This will only get worse in coming years. Sometimes the fine wire does indeed break, usually caused by the deteriorating foam and resulting shifting. Sometimes it's just plain age, especially with the 4kc filters. They seem to get the most use.

Both receivers are well worth having. Whichever you decide on Jay, do yourself a favor: get yourself a few spare gear clamps. They are by far the highest failure item in both sets, a result of both age and over tightening. After you've done it a few times, dropping the front panel is a 5 minute or less job. Re-timing the gears is pretty simple too, as long as you can see. It's more a nuisance than anything, but not something you should have to do very often.

It's never to late to fight communism, after all. Be prepared!

Even here at home.
November can't get here fast enuf for me.

WOW times are a chainging.......again?

Fred

Yup, I am one of those "new age experts", no doubt!

I have had my R-390 electrically and mechanically restored by Rick Mish, and I handled all of the cosmetic restoration myself. And I had my R-390A gone through by Chuck Rippel and it did not need any cosmetic restoration. Although I have been a ham for 40 years, I still know my personal limits insofar as how much repair work I am willing to take on with regard to a unit that can be difficult to service for the unintiated. So yes, I wrote checks to both fellows and was quite happy with the results.

But can someone clarify for me what the heck "new age" has to do with any of this? I don't hang crystals on my equipment to improve it's resonance with the universe, etc. I don't chant ommmmmmm to improve my transmit audio quality. Or is this just a judgemental comment directed at others not willing or confident enough to service their own equipment, such as me in this case? I guess I or any others that are "new-age experts" get no credit for designing and building their own 1000 watt plate modulated transmitter, etc., etc. Perhaps only non-new agers do that sort of thing?

Gentlemen, and Jay in particular, please ignore my recommendations with regard to my personal experience with the R-390 or R-390A; since I honestly do not have the KA1KAQ-sanctioned recommendation of at least 10 years minimum experience with either receiver, my comments as a user are simply not valid here, at least according to Todd.

Oh, I almost forgot; my first operating experience with an R-390A actually goes back to 1973, when I was WA2Oily,Greasy, and Slimey. I had a summer job at Comtech Laboratories and they had an R-390A that I used to play around with during lunchbreaks, etc. That is when I first became tremendously impressed with this receiver, and always wanted one from that time forward. But since I did not own an R-390A back then, let alone serviced one, my comments and/or recommendations still should not count, at least according to the "new age expert" police and high priests.

73,

Bruce

Ahhhh heck when I was at Ft Monmouth in Receiver and transmitter repair, we would listen to WABC for a few hours on the 390A and the distorted audio.
And as an excersize in trouble shooting we would put a trouble in a RX and see how long it took a fellow student to make it work again. AGC problems are hard to find.
As long as you have the manual and a sig gen, and a volt meter, you'll be ok.

If I had the money, I would send mine to Rick Mish just to get it back to factory spec. Time is in short supply for me these dayz. As long as it's close to .2 microvolt sensitivity and the filters work............I'm happy

Phred

Bruce I don't know if I fit that category and ought to be insulted too.

My limitations have always been a matter of not having the time. I also have some generous friends who always have been helpful guiding my projects and even doing some or much of the work. (Including Chuck Rippel, WA4HHG, whom I've known since 1972 when I helped him toward his Amateur license) This does not take anything away from my first-hand experience, and my ability to convey that information to someone else.

The other night I joined a roundtable with three or four stations I had never worked before.  All are longtime AMers but out of my usual signal zone.  One guy is running a pair of 810s into a pair of 4-400s which prompted me to tell the story of my 1953 homebrew transmitter, abandoned and incomplete by the original builder who succumbed to SSB in the time frame.

I picked it up in 1976 from a posting at a local ham store (Comm Center, Laurel, MD, long gone), after two of his friends were settling his estate. They seemed pleased that someone was actually going to complete the set and get it on the air as intended, but I didn't have a clue how to build something up and there was no schematic.

Thanks to a few guys I had met on The Big 85 (you know who you are) I completed it over Christmas break and was on the air in 1977 for quite a few years with it.

I still don't have the depth of technical expertise, and I certainly have even less time now than back then.  

I do not think that makes me any less qualified to comment and venture an opinion on such rigs that I've had some sort of experience with. And where my opinion can be helpful to others, it's done with a sense of encouragement of the person expressing interest.  

g?

Is that the rig you showed me when I was over there? I thought you said it was a commercial transmitter that came out of that old ship-to-shore station on Long Island (band-switching RF deck at least?), modulator section from a Gates rig you parted out, and a power supply you built for it? It was the one with 833s and wires hanging out the back, kind of over in the corner against a wall. I admit, it's been a couple years.

More to the point (and why I bothered to mention it), my remarks above refer to a group of know-it-all types who appeared on the original R-390 email list started originally by Mike W1RC and Chuck back in the mid 90s (I think you only joined that list a couple years ago Bruce, so that would leave you out). Most had some hands on experience with 'radios' but were more likely to parrot whatever they 'heard' (read) on the internet. The term 'non-A' to describe the original R-390 is a clear sign of this new-age thinking, choosing to describe something by what it isn't rather than what it is. Of all the examples that I've seen and all the documentation, never has any R-390 been tagged 'Receiver, Radio R-390 Non-A/URR'. And you never seem to hear folks referring to the SX-28 non-A or KWM-2 non-A, so it appears to be specific to the group.

Anyhow, after a couple years the new experts knew more than the guys who used and serviced the gear for the military over the decades, a number of whom were list members, a couple even having PhDs in different areas. The result was most of the knowledge base leaving the list or going silent while great debates took place on the deadly radioactive meters, proper replacements for the 3TF7 ballast tubes that would meet with approval, and the black crud found inside of the electrolytics. Another great debate swirled around black-paneled R-390As which of course had to have been used by the CIA, NSA, and other 'black' agencies. This despite the fact that the last batch NSA surplussed were still in their original gray paint. No matter, it was all a conspiracy - they paid for custom paint jobs, then paid to repaint them back to gray (and scratch them up) before sending them to surplus.

Then there was the time at Hosstraders when one of these experts proceeded to tell a well-know R-390 man exactly how things were and why, ala internet info. Mike tells the story better than me.

So yes - the 'new age'/misinformation issue is one to avoid when someone is seriously looking for one of these fine receivers and desires to know the differences, what to look for and avoid, etc. And I would be suspicious of accepting advice at face value from someone who had limited experience with the radio, regardless of their own perceived technical skills. Beyond the block diagrams, it's not like any other radio. The R-390 family has enjoyed a great surge in interest over the last decade or so, at the same time the internet and its associated myths were exploding. I know Jay has owned the A model previously and probably knows most of the potential pitfalls involved, but may not be as well-versed in the R-390. It therefore seemed important to me to give him a head's up. If it made anyone feel somehow guilty or inadequate, it certainly wasn't the purpose of my post. Hopefully the knowledge shared here will help them overcome these feelings. It's supposed to be a hobby, after all, not an online ledger to keep track of profit or accomplishments. Let's focus on answering Jay's questions, not making personal attacks.

You described that list to a T Todd!  I was on it for about a year in the mid 90's and had enough. It made me want to puke when the brain dead experts, including the new age ones who would take your money for a "restoration", insisted that only Orange Drops could be used.

P.T. Barnum sure had it right.

Carl
KM1H

I quit that list after one too many discussions on which spray cleaners were best.

The crappacitor wars were interesting! Some beatings of dead horses helped pass time while drinking the morning's coffee and I used the delete key often. In all there is good info in the 390 archives.

So which is better, BBOD's or Orange Drops???? ;D

Craig,

Todd, thank you for your detailed reply.  I appreciate your clarifications to my query.

You are largely correct; the transmitter is homebrew, with the exception of the final amplifier unit that I had heavily modified. The amplifier was manufactured by ITT Mackay Marine sometime in the 1960s, but I did not obtain it from ITT Mackay World Communications here on Long Island, although many of the parts in my rig did originate from that facility after it closed down in the early ‘80s.

The Mackay final amplifier was originally used in either a shipboard or coastal HF installation; I am not sure which. It was essentially a flea-market item, and I have no idea where it was deployed during its time of service.

At any rate, the amplifier was a common-cathode/tuned-grid class AB1 linear amplifier, designed for CW/SSB operation. I extensively modified it for use as a class C plate modulated amplifier, providing it with the correct interfaces to allow it to be utilized with my existing transmitter control, power distribution, protective circuitry, and HV plate and screen supplies. In my opinion, in the original configuration, the MacKay amplifier was poorly designed; for example, mechanically, the layout was a POS and it had no neutralization or parasitic suppression in the final. I added this as part of my modifications. It used a pair of unobtainium Penta Labs tubes; I replaced them with a pair of 4-400As. The 4 KV spacing air variable plate tuning capacitor in the final tank circuit was replaced with a 15 KV vacuum variable, and virtually all of the other final tank and screen circuit components were replaced as well. The sheet metal cooling shroud was redone to change the forced air cooling path and to reduce the overall height of the unit, thereby allowing it to fit within the existing rack opening. The exhaust air is now ducted out through the modified rear panel. The fans and top and side panels were replaced too, as part of the cooling path changes. To a large extent, all that I really retained from the original unit was the front panel and the very robust welded aluminum chassis, the intermediate power amplifier (IPA) stage, the bandswitch, and the final tank coil. The linearity comparator meter was replaced with a grid current meter.

I also modified the IPA, and I had to design and build a separate power supply to provide filament, bias, screen, and plate operating power to that stage. I added an internal class C fixed and grid leak bias supply for the 2X 4-400As. The amplifier only requires about 750 mw to drive it to 1300 watts DC input. It was used to replace my original homebrew single 4-400A plate modulated amplifier I had built back in the late ‘70s that was capable of running 800 watts DC input, and now resides in my garage. The 2x 4-400As provide a superior match to the 4750 ohm secondary winding on the mod transformer, vs. the single 4-400A. After all of these changes, I like to think of this amplifier as really being of my own design.

Yes, all of the wires are still running out of the rear of the transmitter. Due to the limited rack space and the large size of the Gates modulation transformer and modulation reactor I’m using, you may recall that I was forced to install those magnetics outboard of the rig. When my shack was located upstairs, the transmitter was completely self-contained in two separate racks; once the station was relocated into the basement, one of the racks had to go due to space limitations, and some of the larger and heavier components had to be relegated outboard. Necessity becomes the mother of invention. Not what I would have liked to have done, but it is what it is, and it works FB.

I don’t recall if you last saw the rig when I had installed the push-pull 845 audio driver. It is also outboard, being mounted on the rear of the 7-foot rack located next to the transmitter. The homebrewed 1400 VDC power supply for the audio driver sits on top of the large bass reflex speaker that is the station main monitor. At this point, I have essentially no more room left for anything in the shack. Perhaps you are aware that I am restoring a TMC GPT-750 and a TMC SSB rig, and have no idea as to where I will be able to set them up, but I just enjoy working on this equipment.

Please note that I did not take this R-390A issue personally, and trust that you did not either. Again, thank you for the response.

I'm not trying to hijack this thread, so this is the end of the W2XR final amplifier saga.

73,

Bruce

I never had or tried an r390, only had some r390a's.
I worked on a few (broken clamps) as well as my own.
The first one I had I changed the audio deck, installed a small hifi output transformer, which worked well, but then went to the outboard audio, which worked better!

Besides the clamps, and one ballast tube failure, I never did anything to them, and they worked without trouble.

In comparison to the homebrew receivers, the r390a was not quite as good, on very weak signals, they were in the background hiss on the r390a, in the clear on the homebrew.

Since I have NO high end hearing, I used a 5.5kc filter in the homebrew, with a 4.5Kc as the narrow position, I used to use the 4kc the most on the r390a, as 8 was usualy too wide.
5.5 works great for me.

I always wondered what would be a good lube for all those gears and cams, but never had to do anything about it.

The r390 series is likely the best 100 pound receiver ever made....

Brett

Id put it in the top 10 but nowhere near the top. There are several marine grade and foreign examples that are better in many if not all categories.

JN probably can rattle them off in his sleep :o

Carl
KM1H

Singer sewing machine oil is one of the best. it doesn't ever gum up and it's made for metal sewing machine innards which are remarkably similar to internal metal parts in radios.

marvel mystery oil is not as good and I dont know bout if it gums up under heat or not. thats the biggest problem, does it stay fluid in both hot and cold? sewing machine oil is really excellent on that score. As soon as it gums, you have no lube.

What about clock oil?

Anyway, they have modern stuff now, maybe dry lube stuff that does not attract dirt?
I think I have heard of 500 different things that were supposed to be great.....

Brett
 

 ;D ;D

There's that Rohde and Schwarz behemouth, the EK07 as I recall that's quite the radio.  Never was fortunate to have one, but certainly the quality and craftsmanship is tops (and being familiar with the philiosophies of Dr. Rohde, most likely the performance is as well).   I rather like the FRR-59 performance-wise also; however, the presence of an attenuator circuit makes me a bit suspicious of the ability of the front end to handle strong signals.  The Russians made some very interesting radios also which are gradually coming to light.

Certainly receivers like the Harris RF-590, Cubic R-3030, WJ 8716, etc., while not in the 100 pound class will exceed the R-390 in performance in addition to offering more modern conveniences such as synthesized tuning (and even passband tuning, in the case of the R-3030).

Did you ever use a JRC 515 rxer? for a while it was considered very high up in the totem pole. I haven't checked the newer models but I'd assume they are good as well.

Then there's the WJ 8940, well over 100 pounds probably 20 RU (maybe more). The R-390 looks like a toy compared to this receiver.

AN FRR-59B

I had one made under an Arvin contract.

Amazing.  First time I had seen a tube-type PLL circuit.

(http://www.virhistory.com/navy/rcvrs/wrr2-01.jpg)

I remember when H&H surplus in downtown Baltimore had pallets of those stacked 6' tall on each pallet. (I bought 2 R-390As from him for $175 each) he was trying his best to talk me into buying a couple pallets worth for $100 per palletful.

This was around 23 years ago and I was tight on money and also just didnt feel up to humping those heavy mothers out of their basement / warehouse.

they say hindsight is always 20-20 :'(  :'(

And toss in the shipboard version of the FRR, the AN/WRR-2 and -2A. I seem to recall a few high performing Racals and Seimens tube sets during work assignments to Europe and Israel in the late 60's and 70's.

The EK-7 was on a par with the 390 as far as Rube Goldberg mechanicals are concerned.

Carl

Yep,the RA-17 is pretty much the R-390's equal in most respects except reliability.  It's almost as if Joseph Lucas designed the damn thing

Ah, if it were only that simple! Lucas wiring was a pita for sure, but simple to fix. Tedious, but simple. The RA-17 suffers from the Brit's version of Black Beauties (brown, IIRC) along with a whole different concept of 'modular' design. My first one was a spook version made in Maryland so components weren't such an issue, but when I discovered a cold solder joint on a tube pin would require removal of several modules including unsoldering of numerous wires to repair, I learned how to wiggle it juuuust right to get it to work. The latest one fits well in the cabinet you gave me, btw. With just enough room for the SSB converter at the top.

Had a chance to play with one of those while visiting the left coast/PNW a few years back that came out of the batch Hank KN6DI brought over. Certainly an impressive rig with performance to match, but being nearly the size of a dishwasher and requiring 2-3 people to move, it was definitely on par with the big Nationals for portability. The EK07 is also butt ugly (not that the R-390 family has any beauty queens) and reminds me a lot of a piece of 1950s Xray gear. Labeling and paint is a bit like the commie gear seen in recent years.

All things considered, the R-390 is certainly in my top 2-3, certainly tops for performance in its class. Can't imagine trying to find chips for some of those WJ rigs or anything for the EK07.

What a waste.

(http://frrl.files.wordpress.com/2009/02/r390_depotpallet.jpg)

http://frrl.files.wordpress.com/2009/02/r390_depotpallet.jpg (http://frrl.files.wordpress.com/2009/02/r390_depotpallet.jpg)

Hmmmm,
I find this post VERY interesting. Where to start??????
I use an R390A and love it. I also have a 75A4 done up by Howard Mills and I also love it.
Two different receivers for 2 different band conditions.
When u asked your question Im sure u ment which receiver is good for the average ham.......not looking for explanations that have nothing to do with the average ham. I find it funny that some folks have to show off their so called knowledge of either receiver, dont let them scare ya......considering BOTH of them  are great.
I would bet if I hid both receivers behind a curtain and asked the "experts"  to tell the difference between the two under average ham usage.......they couldn't.
Another point of this post..........NO ONE IS ATTACKING ANYONE!
Opinions are like a$$ holes......everyone has one!

JMHO.......

Bill


Let the flames begin!!!

JUST KIDDING, right Bill??  ;D

And if I am not mistaken, these pallets of R-390s were frequently dumped in the ocean, either by cargo aircraft or by ship.

What a waste, indeed.

73,

Bruce

I was always curious -  what unit replaced all these R-390s that were used in military service?

Nothing in some cases, since HF was no longer used. In other cases it was some of the RXs from Racal Watkins-Johnson, and probably others.

IMO that post was as childish as his avatar ::)

I think in many cases the communications traffic previously handled by the obsoleted HF circuits shifted over to satcom links, and later to fiber optic comm links.

73,

Bruce

The R-1051 and later, the Racal 6790 were the big dawgs in the post-R-390 era.  Additionally, the mil version of the WJ 8716/8718, and the Cubic R-3030 were used in smaller numbers.

Yup,
Just kidding with a little "edge"  ::)

Bill

Bruce,
         the ones he was trying to sell me for $100 / pallet were the FRR-59s, not the 390s.

You haven't experienced ham radio to its fullest if you haven't spent a weekend aligning a FRR-59  ::)

In production each module was aligned seperately on a custom built jig. Once assembled into a functioning radio the final test tech merely had to verify spec parameters.

My first job at National was in Malden as a module tweaker and I was soon climbing the walls. Luckily I was out of there in a few months when a slot opened in the Service Dept in the National Radio division in Melrose.

Carl

Lord have mercy on your soul.
I was scared of the damn thing.

It was nice to have those pullout drawers AND tilt pivots to work on either side though, AND to have the sub-assemblies you could raise from the main chassis. 

Chuck W3FJJ has either this one or a 525.
One post-Timonium party he had, I spent hours using it and it was a very nice receiver.  That was the same fester that you and Dean-O the KNX did the Infamous Belly-Bump, do you remember ?

The NRD "felt" more like a gussied-up Kenwood R-1000 than a commercial rig.  It was better sounding than it's main competitor at the time, the ICOM R-70, a model now seldom seen on the used market. I think its descendant, the R-71, sold better so more of them are kicking around.