R390 OR 390-A

[WV Hoopie]

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

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?

Craig,

[W2XR]

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

But can someone clarify for me what the heck "new age" has to do with any of this?

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?

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.

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

[N2DTS]

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

[KM1H]

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

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

Carl
KM1H

[N3DRB The Derb]

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.

[N2DTS]

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
 

[w3jn]

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

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

Carl
KM1H

 

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).

[N3DRB The Derb]

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.

[Steve - WB3HUZ]

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.

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

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

Carl
KM1H

 

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).

[WA3VJB]

AN FRR-59B

I had one made under an Arvin contract.

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

[The Slab Bacon]

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  

[KM1H]

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

[w3jn]

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

[Todd, KA1KAQ]

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.

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).   

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.

[W1GFH]

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.

What a waste.



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

[KC2IFR]

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!!!

[w3jn]

I find it funny that some folks have to show off their so called knowledge of either receiver,

"experts" 

Opinions are like a$$ holes......everyone has one!

NO ONE IS ATTACKING ANYONE!

JUST KIDDING, right Bill?? 

[W2XR]

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.

What a waste.



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

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

[W1GFH]

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.

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

[Steve - WB3HUZ]

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.

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.

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

[KM1H]

I find it funny that some folks have to show off their so called knowledge of either receiver,

"experts" 

Opinions are like a$$ holes......everyone has one!

NO ONE IS ATTACKING ANYONE!

JUST KIDDING, right Bill?? 

IMO that post was as childish as his avatar

[W2XR]

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.

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

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

[w3jn]

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.

[KC2IFR]

Yup,
Just kidding with a little "edge" 

Bill

[The Slab Bacon]

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.
What a waste.

What a waste, indeed.

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