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Power Pak SMG-40 Stereo Generator

S

Studio1

Hi all..

I have a "Power Pak" SMG-40 stereo gen sitting here... working perfectly but I need some info on it.

The guy we bought it off said he'd supply the manual but so far nothing and I need to find out what the various
jumpers are on the main board, which ones are for the pre-emp etc.

Any information would be greatly appreciated, including the history of the manufacturer as I can find nothing on the net.
 
Surely someone has heard of this machine, or the company? It came from the USA ... was 110V when it got here, had to reconfigure the transformer to 230V.

Bump.
 
Fascinating! I have a Power-Pak 40 watt exciter sitting on the shelf--was built in the 80's here in the states.
Wonder if there is any relation to this manufacturer?
 
TomT said:
Fascinating! I have a Power-Pak 40 watt exciter sitting on the shelf--was built in the 80's here in the states.
Wonder if there is any relation to this manufacturer?
Click to expand...

I'd say it's the same manufacturer. Have you got any info on the company - which I presume is long gone?

This unit looks kinda 80's - it's got a very "home-made" engineering look about it.
 
Yes, company is long gone. They were down in Texas somewhere. Exciter matches your description as "home built,"
is 5 RU with a big meter in the center to measure output, current, volts, small LED meter on the left for modulation.
Makes a maximum of 30 watts out, real pita to work on, as it has a switching supply buried under another circuit board.
One is on the air in town on a 10 watt station, I have another on the shelf I need to get to someday.
 
Was that thing maybe made by the same fol;ks who made the Micro Controls STLs? (Not the Micro Controls who make elevator parts, I don't think)?
Thery also tried but I don't think ever marketed the same idea as the TFT 'reciter'.
The STLs were amazing performers when they worked, but had some QC problems with components.
 
If I am think of the same unit, the Micro-control STL's were made by a fellow who quit Marti and set up his own shop in Cleburne in the late '80's. Made them for about 5 years, then the company vanished (remember installing one that was bought about 1993). The Micro-control had the interesting feature in that you could push a button on the front panel and cut the output power from around 10 watts to under a watt. They had heat problems--the one I installed in '93 would not put out anything near full power until we installed a pair of 4" fans on the back of the rack blowing across the heat sink.

(Incidentally--good trick to remember for crowded racks--I have a couple of 4" fans on the back of my transmitter equipment rack to keep a pair of 606's cool. They will run without them, but it sure helps the life of the regulators on the back panels.)
 
Ok I have uploaded a photo of this machine:

9h3yxi.jpg


This was taken at night so not the clearest but you will get an idea.

I've left the top off as well so you can sorta see inside.
 
I've never seen one of these, but the Power Pak logo and the general layout and interior design show this is a sister unit to my Power Pak exciter. I'll try to remember to pull the manual out on the exciter tomorrow & see if there is any old telephone number or address in it (believe there is).

As I've noted, this equipment was made in the early '80's. Company long since gone.

I can't see any jumpers in the photo, but assuming they are near the front (hence behind the panel) I suspect they are for selecting flat/50/75 usec pre-emphasis.

Looks like the only adjustments are front panel. If you can find a 8000 manual (Bob Orban may still have that on the Orban site), there is a good section on setting pilot phase and l-R gain using a tone generator and scope. Complete with screen shots of the scope, so that you know what to look for. The same procedures will work just fine on this unit (assuming it is working normally).
 
Thanks Tom...

Yes, the unit is working very well, and I've found at least two sets of jumpers on the board. The ones which I believe are for pre-emphasis are closest to the front of the board, and there are a set of jumpers further towards the rear.

It would just be nice to know which is what and how things should be set. I do like to have manuals for all of my equipment.

The majority of adjustments are on the front panel, including many that don't need to be on the front panel!

Pilot phase and injection are hardly adjustments that need to be continually re-adjusted!

Where the logo is on the front panel there used to be a snazzy cast-metal badge of a similar design but it seems it was only glued on and it fell off a few months ago.

If you can dig up any info on the company I'd be interested to know.

Cheers.
 
Back in this era, some exciters had a "hot" chassis; so the jumpers may float or ground the composite output.
 
Hmmmm..

My Power-Pak manual just has the telephone number 817-430-1700, which is somewhere near Denton, Texas. No address or other info in the manual--crummy looking thing typed up with hand-drawn schematics and a blank paper cover. Phone number doesn't cross-reference to anything in these reverse-lookup searches--but could just as likely come up as a Chinese-Mexican restaurant. I think the company is long gone.
 
Thanks Tom, I might just have to get keen and remove the board to identify what part of the circuit the various jumpers are in and draw out a rough schematic for reference.

The guy I bought this off promised me the manual for it but it never arrived and repeated emails requesting it have gone unanswered.

Ah well.
 
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