ETO ALPHA 77SX Linear Power Amplifier, 4KW OUTPUT+, MINT

This is a very rare and hard to find linear amp by ETO Ehrhorn Technological Operations, model ALPHA 77SX. The following changes were made to the amp by me personally.

An electronics engineer and ham radio operator since 1981, and a ham radio dealer since 1993. Replaced the main transformer with the original Peter Dahl ALPHA 77S-4.

This gives the amp 4KW plus output. This was ordered direct from Peter Dahl. This was a plug and play installation. Connectors and mount holes were the same as stock.

We were complimented for a job well done by the guys at Peter Dahl. Our amp photos are on their website.

Replaced the power supply filter condenser with a 5KV/35MFD instead of the stock 4KV/25MFD. I ordered the original Condenser Products MOC5M35ES. This was needed in order to handle the increased 5KV plate voltage.

This cap was ordered direct from Condenser Products. No mods, bolted right into the old holes. Replaced the diode rectifiers with a string of diodes capable of 9KV at 3 AMPS. Uses four series strings of nine 1N5408 diodes each for a total of 36 diodes. The original diode bridge rectifier has very limited voltage and current headroom and could not handle the increased plate voltage.

Replaced the left multimeter faceplate as the original red lettering used for power output had been erased due to age. I have an extra faceplate that will be included. Look at fotos to see what the old faceplate looked like. The red lettering is completely vanished!

I have used this amp for the past 3years and never had an issue. Tunes easily up to 4KW output with 130140 watts drive. Looking at the fotos you will see that the cabinet is mint condition. I have uploaded 22 photos total.

Please see them all carefully. Included are the manual and power cable. The amp is wired for 220 Volt operation. You can easily change the jumpers to other voltages.

The process is described in detail in the manual. I will remove the tune knob from the front and then pack the amp in a custom wooden box. I have great experience so please don't worry. The safest way will be by courier. I have an account with TNT.

Let me know if you need another transport method. If you have any questions or need more photos please ask. I can be reached at +30-6944320600 anytime 0700 to 2200 UTC. Add a map to your own listings. The item "ETO ALPHA 77SX Linear Power Amplifier, 4KW OUTPUT+, MINT" is in sale since Friday, September 29, 2017. This item is in the category "Consumer Electronics\Radio Communication\Ham, Amateur Radio\Ham Radio Amplifiers". The seller is "2way-radioexpress" and is located in Athens. This item can be shipped worldwide.

Brand: ETO ALPHA
MPN: Does Not Apply
Max. Output Power: 4000
Supported Modes: AM
Model: ALPHA 77SX
Country/Region of Manufacture: United States