Allied 498 Receiver just arrived - couple questions

tuberadios69

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I just picked up a nice Allied 498 receiver which is basically a somewhat stripped down Pioneer SX-2500. It uses four 8V 0.25 amp bayonet lamps for the dial illumination. Does anyone know of a source for these? I subbed #47 bulbs which are 6.3V 0.15 amp but would eventually like to install exact replacements. There was no # on the old lamps, just the voltage rating and "Stanley" (brand?) and what appears to read "H.D" below all that.
The receiver also has an inoperative automatic motor driven dial scan feature. Tuning manually is a bit stiff so perhaps I'll need to lube bearings around the flywheel or the guides. Anyone have experience doing that with either this Allied or the Pioneer (SX-2500)?
The receiver seems to work pretty well on FM although the right channel has a tiny bit of background noise (on any input). I'm running it right now with headphones just in case some small electrolytics need reforming. The stereo indicator wheat bulb is out and looks to be a real pain to get to (I have replacements). The dial indicator/pointer also doesn't illuminate. It too looks like a pain to disassemble and fix. Any comments from any of you with experience here would be greatly appreciated!

This pic came from the seller's description. I'll post a better one with the illuminated dial later.

Allied 495 front panel.jpg
 
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Here's a picture with the new dial bulbs installed. Roscoe couldn't resist the photo op. too. Would be great to hear from any of you with experience dealing with the Pioneer SX-2500 auto tuning mechanism . . . .

Allied 498 receiver and Roscoe.JPG
 
As a teen, I collected hundreds and hundreds of audio spec sheets/brochures while visiting stereo stores in the Wash DC area during the late 60's through 1970's (much to the chagrin of store personnel). As a result, I am fortunate to have a massive data base in binders that I've kept all these years. My Pioneer SX-2500 brochure indeed confirms that the Allied 498 was a very slightly stripped down version of the SX-2500. I confirmed this when I opened the 498 to replace the dial lights. Same FM boards (crystal filters in the IF section!), same output section and power supply caps, etc. just no provision to add the MC phono adapter (on the side panel) or the wired remote for FM/AM auto tuning. And, a teeny bit less flexibility like no switch to separate pre and main amp sections, no muting threshold knob and no multiplex filter switch but, the Allied does have a "tone defeat' pushbutton which the SX-2500 lacks. I'm really glad I bought it but sure wish I could get the auto tuning mechanism up and running. I'm surprised no one has commented on that.
 
As a teen, I collected hundreds and hundreds of audio spec sheets/brochures while visiting stereo stores in the Wash DC area during the late 60's through 1970's (much to the chagrin of store personnel). As a result, I am fortunate to have a massive data base in binders that I've kept all these years
I used to circle the numbers on cards in the back of Stereo Review and Audio magazines. I had a lot of this stuff too. It all got ruined because it was sitting on the floor of my closet. This closet backed up to the bathroom. A pipe started leaking and all of these brochures, magazines, catalogs, records, etc. wicked up the water and ruined it all. :( Seeing what some of this stuff is seeing for now, it is sickening.
 
The Allied 498 is a very underrated receiver! I've had 3 of them, including the one pictured. It's part of my early 70's vintage stereo system! The 498 is a combination of the Pioneer SX-2500 and SX-9000 receivers. I've spent way too much $$$ over the years keeping this 498 in good operating condition. My last service consisted of a partial recap (35 capacitors) to cure an annoying turn-on pop. But, it did the job and I'm happy! I replaced the incandescent dial bulbs with led's, giving a beautiful royal blue hue. I also built a custom wired box that connects to PHONES B jack, which was electrically modified so I can manually operate the tuner from up to 20 feet away. Kind of like the box that was available for the SX-2500, but without the volume control. The tech who did my recap also performed a complete power output test. Topped out at 38 watts per channel RMS at 8 ohms. The original specs were 84 watts RMS, but at 4 ohms. I thought it would do at least 55 watts at 8 ohms. Still, those "honest" 38 watts are enough to drive my very efficient Realistic Optimus-6 speakers with Jensen SG-220 speakers installed!

Have fun with your 498!
 

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The Allied 498 is a very underrated receiver! I've had 3 of them, including the one pictured. It's part of my early 70's vintage stereo system! The 498 is a combination of the Pioneer SX-2500 and SX-9000 receivers. I've spent way too much $$$ over the years keeping this 498 in good operating condition. My last service consisted of a partial recap (35 capacitors) to cure an annoying turn-on pop. But, it did the job and I'm happy! I replaced the incandescent dial bulbs with led's, giving a beautiful royal blue hue. I also built a custom wired box that connects to PHONES B jack, which was electrically modified so I can manually operate the tuner from up to 20 feet away. Kind of like the box that was available for the SX-2500, but without the volume control. The tech who did my recap also performed a complete power output test. Topped out at 38 watts per channel RMS at 8 ohms. The original specs were 84 watts RMS, but at 4 ohms. I thought it would do at least 55 watts at 8 ohms. Still, those "honest" 38 watts are enough to drive my very efficient Realistic Optimus-6 speakers with Jensen SG-220 speakers installed!

Have fun with your 498!

Pretty cool looking vintage system! My 498 is running well now with an especially good sounding FM section. The motor driven mechanism still isn't functioning so I'm wondering if I should be replacing a cap or two or perhaps a resistor associated with that system. Have you ever had to work on that section with any of your previous three units? BTW, assuming the 498 has the same amp section as the Pioneer SX-9000, it should clip at about 50-55 watts RMS per channel (8 ohms) but it is the lower frequencies (20 to 30hz) where the power supply limits the maximum available RMS power (at under 1% THD) to 35+ watts RMS as measured by your tech. The higher frequencies tend not to suffer that slight decline and maintain low THD up to 50 watts or so in the vintage magazine test reports I've seen (Audio magazine for the SX-9000). That's still a pretty powerful amp!
 
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Hello, does anyone have a schematic for an Allied 498?mine has a burned resistor that my tech could not make out the colors .
 
Well if it is the same as the SX2500 or the SX9000 then the site hifiengine.com has those service manuals and might be of help.
 
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