{Collins} Collins 828E-1 broadcast transmitter



FOR SALE: Collins 828E-1 Power Rock AM Broadcast Transmitter
Have a complete transmitter as pulled from working service several years ago
It is clean and unmolested.  Currently tuned to 1310Khz
Runs a pair of 3cx3000a7 tubes, one in the RF final and one in the power supply/PDM modulator.  If you don't know what a PDM modulator is, its a DC switching supply with the ability to modulate the audio onto the DC via the switching supply at a 70Khz IF.  It is then low pass filtered stripping off the 70Khz leaving just the raw AM modulated DC.  Its super slick and you don't have to worry about losing a hard to find modulation transformer.  Efficiency is very good so its much cheaper to run long term. The interesting thing about this transmitter is because it is PDM modulated, the power is fully adjustable from about 500 watts up to 5KW.  If you retap the dual winding transformer (3 Phase) to lower the voltage it is possible to run anywhere between 250 watts to 2.5KW.  Modulation capability is upwards of 150% so this should make someone a real barn burner on 160 or 80 meters if you have the ability to reset the final tank components.  This has a band pass output network, so it is ultra clean with no measurable spurious outside of its operating frequency.
Looking for $8500. or may take offers including trade for Collins S-Line, or other interesting AM gear.  Its on a pallet and can be loaded on a truck and shipped to your door.  Delivery to Dayton Hamvention may be possible, 
Pictures available, please email me off line.
Thanks & 73, N8BX
Fred






This archive was generated by a fusion of Pipermail (Mailman edition) and MHonArc.