Pioneer SX-2500 Receiver ...

[Chip - HP]

This morning I picked up (and it was heavy ) a Pioneer SX-2500 receiver manufactured in May, 1971 according to the SN (RE 19944) ... cosmetically, it's in great shape ... stylistically, it's not as pleasing as the silver faced Pioneer receivers ... per other threads, the power is 72 wpc ...

The bad news ... the wired tuning remote and the speaker plugs are missing ...

It has two Phono connections ... one marked MC/MM ... and the second has 2 pairs of female RCA connections ... one marked MM (which has black tipped plugs protecting the connections) ... and the other marked Cer ... does Cer stand for ceramic? ... what do MC and MM stand for? ...

There is also a switch titled PRE & MAIN ... and the choices are ... Separated ... and Inter-coupled ... to the right are pairs of female RCA connectors for the PRE OUT and MAIN IN ... w/o the the silver "U" connectors that one normally sees ... I am guessing that I should have the switch on Inter-coupled for normal use ... if that's right, why would I want to switch it to Separated ? ...


Apparently, this receiver was reviewed in the Oct. '71 issue of Stereo Review ...

[KingBubba]

Nice find, I have the little brother, the SX-990. It is pure Pioneer. You may not have noticed but the tone controls are split into left and right. The tuner should be very sensitive. The pre out and amp in can be used in different ways. You can put a processor (EQ) into that loop, or you can split your output to two amps, or just to another amp. This allows you to use your receiver as a preamp only. The phono input allows for the use of a cartridge with a moving coil, a moving magnet or a ceramic, The black plug is a shorting plug which helps keep noise to a minimum from the phono preamp. You have a very nice old Pioneer. A little Deoxit and a good cleaning is probably in order but it is built like a tank and probably has some life in it yet.

[Chip - HP]

Thanks for your input ... KB ... is my assumption about switching it on Inter-coupled for normal use correct? ...

While cleaning it ... I discovered an opening (1.5" x 3") on one of the sides with 2 tube-like (they have pins) pieces inside(see pic ... I removed the smaller one (which says ... Cds Lamp unit ... on the beige top) to get a better look at it) ... what are they? ...

[jwrags]

Chip:

I have one of these with the remote and manual. From the manual:

For remote control of FM or AM "Auto" tuning and volume adjustment, connect the REMOTE CONTROL UNIT to the REMOTE socket on the front panel, and connect the CdS UNIT to the 7P socket on the right side.

The manual goes on to say turn the volume down on the SX-2500 and use the remote volume to control the volume.

I don't currently use mine, but it is a keeper.

Best
John

[buckleboy]

I have one of the SX-990 units. Very well built and packed with features. Pioneer made some substantial gear back then.

You can get the Pioneer speaker jack adapters for those here for $8.50:

http://www.vintage-electronics.cc/vparts.html

[Chip - HP]

Originally Posted by jwrags

For remote control of FM or AM "Auto" tuning and volume adjustment, connect the REMOTE CONTROL UNIT to the REMOTE socket on the front panel, and connect the CdS UNIT to the 7P socket on the right side.

The manual goes on to say turn the volume down on the SX-2500 and use the remote volume to control the volume.

Thanks, John ... what is the Cds Unit? ... I didn't check it but I am guessing the 7p socket is the smaller piece (on the left in my pic) ... so what is the function of the other larger piece (on the left in my pic)? ...

[Chip - HP]

Originally Posted by buckleboy

... You can get the Pioneer speaker jack adapters for those here for $8.50:

http://www.vintage-electronics.cc/vparts.html

Thanks ... fortunately, I have accumulated a few extras ...

[jwrags]

Chip:

The smaller socket on the left is indeed where you plug in the CdS UNIT. If you don't plug it in, the remote will not work.

The larger socket to the right of this is where you plug in a transformer for a Moving Coil cartridge. Pioneer Model PP-402 MC Transformer, separatry available

Capitalization and misspellings are from the manual.

Best
John

[Chip - HP]

Originally Posted by jwrags

The smaller socket on the left is indeed where you plug in the CdS UNIT. If you don't plug it in, the remote will not work.

The larger socket to the right of this is where you plug in a transformer for a Moving Coil cartridge. Pioneer Model PP-402 MC Transformer, separatry available ...

Thanks ... are there model #s on the tuning remote that plugs into the front and/or the Cds Unit that plugs into the side? ...

[jwrags]

No model #s that I can find either on the units or in the manual. I think in Dr Strangelove's scans there is a picture of the remote on top of the receiver.

Best
John

[Chip - HP]

Originally Posted by jwrags

No model #s that I can find either on the units or in the manual. I think in Dr Strangelove's scans there is a picture of the remote on top of the receiver.

Thanks ... I saw that pic ... was hoping to track down an orphan tuning remote using a model # ...