The AM Forum

I found a really nice condition Hammarlund "Super Pro" for sale.  What is the value and desirablilty of this unit?  I think it is the model with the built in power supply but will look it over more carefully on Friday.  Any input would be appreciated and I hope I posted this in the right section.  Thanks.

Any SuperPro is desireable.  Many prefer the SP-600 (the one with the internal PS) but the separates (SP-100/110/200/210/400 and BC779/BC1004) are tops for AM use, even better than the SP-600.

Value would depend hugely on condition.  Usually the separates go for quite a bit less than the SP-600.  An early SP-100, or a really nice SP-400 with the cabinet might go for $300, tops.  The BC779/BC1004 (SuperPros in uniform, WWII vintage) are about a hundred bux or so.

The SP-600, if it has its original cabinet can bring >>$600 if in nice shape.

The only tube receiver I have is an SP-600.  It's built of great quality and works FB on AM.

As far as sheer performance, I like the receiver in my FT-102 better for both AM and ssb, but that is not a fair comparison.


I replaced all the old black beauty caps in mine. Check to see if it has these old caps. They become very noisy and must be replaced.  Getting at some of these caps is a real job, especially when they are located under I.F. cans.

It's a good receiver to buy, use, look at and work on.

73,

T

I will look closely and get the exact number and try to post it here Friday night.  The case is super, super clean, minty I would say.  I will look for the power supply.  What if the main part is minty and I can't find the power supply?  Would it still be desirable?  Thanks. 

It depends on your skill set as to whether lack of power supply is a dealbreaker. It's not difficult to build an external supply, but the umbilical cable and all that is why the price is lower on pre-SP600s.

For AM reception the variable selectivity is a benefit with the earlier receivers, since you can tailor it to conditions.

But there's plenty of merit with just the feel and the look of the SP600, and the audio quality is very good with either the internal output or through the use of the diode load feeding an external amplifier.

Here's what an SP600 sounds and looks like, as you check which model you've got your eye (and ear) on.


http://www.youtube.com/watch?v=PNtIzVm6lZY (http://www.youtube.com/watch?v=PNtIzVm6lZY)

I use a BC1004 (military version of the super pro) for my main station receiver.....  that being said, it is a very good high fidelity receiver IF YOU USE AN EXTERNAL AUDIO AND NOT THE BUILT-IN AUDIO AMPLIFIER.

- HOWEVER -

It is not a good receiver for difficult conditions.  The skirt selectivity is lacking.

Most of the time, the receiver is sufficient.  When I need good skirt selectivity, I power up the software defined radio (soft rock and PowerSDR software), and that will out perform anything I've ever used...sort of the best of both worlds.

If you have no power supply, don't sweat it.  Building a power supply is not difficult.  There are number of wires which run between the power supply and the receiver.  I made up a cord using multiple individual wires, and tie wrapped them together.

Currently, both of my super pros have been completely converted to solid state, but when they were tubes, I used the home brew power supply.

I may have a "real" super pro power supply kicking around here, which I will be happy to give to you if you come and get it.... let me know !

Regards,

Steve

Now be honest, Steve: you built the umbilical using multiple individual clip-leads tie-wrapped together, right?  ;)

The Super-Pro's I have had my hands on would make good shortwave broadcast receivers, but not ham receivers.  My main objection is their poor frequency stability,  inherent to the receiver due to the design of the tuning capacitor mechanism.  Even when receiving AM with a wide passband I want my receiver drift-free.  I have used a couple of SP's, one borrowed and the other, one I was repairing for a friend.  Neither receiver, even after staying on for hours, would ever settle down and stop wandering in frequency.  One of these was a WW2 era military version and the other was a SP-600.

This was about 25 years ago so I don't remember which, but one of those receivers had paper capacitors that looked a little like bumblebees, but instead of glossy black the plastic cases were made of some sort of brownish-grey composition material.  Those things tended to have cracks in their cases with oil (not sure if PCB or not) dripping out, and they all showed electrical leakage.  The ones under the RF amplifier tubes were all but impossible to gain access to and replace.  I swore right then that I would never own a Super-Pro.

I've used both a 200 and 400 and never noticed any drift problem for AM use. Never tried them on CW, but I could copy SSB OK fine.

Get the receiver. If there is no power supply, get it anyway. You can always find one later. The Super Pro was the premier pre-WWII receiver and the best sounding receiver I've ever used (no mods or using external amps). 

You won't regret getting one.

Ok, these guys are all messin' with you.

It's not very good, it looks good   but don't be fooled... it's made by Hammarlund, and all of their receivers follow the same theme. The rack panel, and big round dials? Nice, but what do they really do? Bah, mere eye candy.

What I'd do is to pick it up, and send it over here. I'll find a use for it as a door stop (I have a big heavy door to hold open in the summer) and just forget about it. I'll cover the cost of taking it off your hands... just let me know... alright then?

Good, that's settled.  ::)

                     _-_-bear

Please, don't send it to Bear....  he will scare it and it will not be happy....  send it to me. I'll treat it nice.

klc

Excuse my ignorance here.  I know a lot about guitar amps but nothing of this type of gear.  So this is just a radio receiver not a ham radio correct?  I am guessing it only picks up AM bands?  Any basic info would be appreciated.  I will try to post a picture Friday.  Seems like this would be a great conversation piece, and a nice bit of eye candy for a cabin or lake house?

Please do post a picture...

Yes, it is a RECEIVER.
It will not transmit.

It is a nice receiver, will receive AM, CW and SSB (with the use of the BFO).

General Coverage type, which includes the ham bands and the CB bands, and foreign broadcast (what is left of that)... and regular AM broadcast stations.

So, yes it is a nice conversation piece, but better when turned on and sound is coming out of the speaker (the one you attach to it) when there is a LONG antenna on the antenna terminals...

               _-_-bear

If it's the earlier Super Pro, it's basically a pre-WWII design, general coverage short and medium-wave receiver. They have a nice push-pull audio output section (pair of 6F6s) that will drive a large speaker nicely (10-12 watts IIRC). Easy to tell by the meter in the center and smaller dial windows (roughly 3 inches square). Separate PS.

If it's a later SP-600, it's an early 50s design with larger tuning dial windows (about 4" square), larger round knobs, and the meter mounted to the left. A more advanced and refined receiver, but lacking a bit in the audio section with only a single 6V6 output tube good for maybe 2-3 watts out. Built in PS.

While not the 'state of the art' by any means, both are, IMO, excellent receivers in their own way. The SP-600 is great for band cruising, the 200 series is great for AM and SW broadcast (or amateur) listening. Neither should have a big issue with drift provided they are in good shape electrically and the correct tap is selected on the transformer of the SP-600. Mine drifted all over hell and back until I changed that.

Is 'minty' the color of the cabinet?  Or is that a guitar term?  Sounds like something bear would say.  ;D

it's quite the ebay rage to say "minty" if something shows up that hasn't been underwater for 4 years shows up, i.e. it actually looks ok.  ::)

Dude. you just wanting to know if it's flippable, yes?  ;)

Personally I prefer tall slender blondes... but to each his own  8)

I think the Derb nailed it!!!

Yup.

Yes, I'll admit I would probably flip it.  But if it is ultra cool I would keep it.  Yes, minty is a term like "mint condition" etc... 

They ARE ultra cool, especially the old buzzard black wrinkle jobs.

I've seen pics of Derb's former minty black crackle Super Pro, very FB OM. I wonder if he has any tips on resto. My BC-779 is starting to get a bit noisy during warm up; I recapped all visible waxies in the underside and AF sections but not inside IF cans and RF decks.

http://en.wikipedia.org/wiki/Hammarlund_Super_Pro (http://en.wikipedia.org/wiki/Hammarlund_Super_Pro)

on the crackle, use GOJO hand cleaner ( the white stuff) without pumice, U will b shocked and awed how much dirt and guck hides in little tiny crackle cracks. rub in generous amounts using clean shop rags. keep at it until your rag starts coming off clean, move to next area. the gojo acts as a soap and a lube at the same time, so you wont be polishing off the tops of the little bitty crackle ridges as you rub. gotta keep your rag wet. You can also add a little hair conditioner to the gojo.

it's been 15 years since I've even seen a SP schematic. The flatwound voltage bleeder rx in the pow-pow-power supply is suspect, if it's only doing it on turn on and shortly thereafter. Use 500 volt caps in that thing, the voltage soars when you first apply power to it. ask Huz about the pitfalls of using 450 volt jobs. The SP 400 I gave him blew a lytic, probably due to a turn on surge. I think the SP 110 used a wet lytic, which in the day were much more forgiving of
turn on surges. I love it when dudes try to reform a wet can cap...which dried out 40 years ago....bone dry   :D

There is one area where the SP 200-400 shines - operation in a strong RF environment. They have a very strong resistance to rf overload.

Frank, if'n you got sum high power resistor mounts, just ditch that flat bleeder/voltage divider and use some good wirewounds
in it's place and tie in sum 500 volt filters. I bet that will do it. the key is it's only doing it on turn on.

I have about 200 rx mounts of all kinds, lemme know if you need any and I'll send ya some.

 

Thanks Derb, I'll check out that flatwound rx on the skizmatic to see what it wants.

I remember it's also a voltage divider as well. I think ya get yer 6F6 bias and yer screen voltage offa that one RX stack.   those things were used by the hundreds in bcl table sets. They almost always have some kind of problem with em. Cheap nasty bad.

Yar, the SX-28 I resto'd a few years ago used one as a voltage divider within the onboard PS. I replaced it with 3 power resistors, as I recall.

GOJO!

Back in 1968 I worked part time at an auto parts store after school. There was a counter guy there named "Tiny" and he was an absolute wise-guy.  He weighed about 300 pounds and took no crap from customers.

There was a customer who came in every few days to buy one of those large tubs of white creme GOJO hand cleaner. Tiny finally couldn't take it any more and said to the guy, "Whad'ya ya do with this stuff, heat it up, spin it and stick your d**k in it?"    The guy looked shocked, then got pissed and left. He never came back.... ;D ;D   Tiny almost lost his job over it.

T

Gee was this Tiny the guy who worked in the speed parts store on the pike?

I took a closer look at it yesterday.  Not as mint as I remembered.  They had more light in the basement.  It had been rack mounted at some point.  It did have the external power supply.  I didn't want to mess with it and it sold for about $120.  Thanks for all your info....

What?? The rack-mounted, external PS version???...you mean the extremely rare 007-OSS model designed to be dropped by parachute behind enemy lines during WWII...?? You let it go for $120?!? One just like it sold for $1.5M USD at Christie's in  London!!! (I think Joe Walsh bought it) Woah, tough luck! :)

My SuperPro came without a power supply and I wanted to get it operational FAST so I went down to the ESS store here in Manchester NH which has racks of old test equipment and looked for something that might have an appropriate transformer. I found a Ballantine RMS voltmeter, a big old rack mount unit and gave Pete 10 bucks for it. I simply took it apart, stripped parts and added a few components and presto - instant power supply. Of course that was 4 years ago and I never got around to making a real supply and it has not exploded yet so...there it sits.

Mike WU2D