Beautiful Collins 51J4 Receiver, Ser. No. 1221. All 3 filters are installed. A Treetop Circuits
Product Detector (plug in adapter) made for the 51J4 receiver is installed and this receiver is a SSB wonder and with great AM. Product Det. Info as follows:
SB-51 Product Detector / SSB Adapter
This is the current SSB adapter for the 51J-3, 51J-4, R-388, and R-388A receivers. The product detector circuit is identical to that in the PD-3. The AGC circuit now uses a separate AGC amplifier for SSB, which provides a better "hang" characteristic. A dual-time-constant circuit resists blocking when impulse noise is present. AM performance is unchanged.
SB-51 Product Manual, http://www.treetopcircuits.com/docs/SB51Manual.pdf
Also installed is a time delay solid state rectifier in place of the regular rectifier vacuum tube, made especially for this type receiver.
I also include an expensive spinner knob with calibrate legend to 51J4 dials. Original knob is included in case you want to return tuning knob to original. All covers and tools are present. Beautiful case with handle grips built into each side and a snap lock cover. Receiver is aligned and tubes all check in the green or were replaced. Complete Manual and schmetics plus all info for the TreeTop Product Detector. One very hot General Coverage Receiver.
Price is $800.00 Plus shipping. I have special boxes and packing for shipping this heavy receiver.
Thanks for looking, Roger K8CIX