I bought one of these items on Epay:
https://www.ebay.com/itm/234728817137?epid=1119242095&hash=item36a6ed81f1:g:IroAAOSw5dNjRDYJ&amdata=enc%3AAQAHAAAAwBhG775IeMLhhW%2BjI5OYdz3wYCMXyaxcpHq1M6XNTAExxy9Wj1NZ1n%2F%2BSi8K%2B1e37yPpYKm1fsqYU0BKd4yi71cE9hNxaSTsDLtU6RFMkzfVYpgdDLkmA5iLAEQVj64s%2Bexa%2BkhwmMXWUMcNc0%2BvtqJL5Wc89CEsyIiO%2BHpSpH2VC6t7UdricbwWds%2FrZry4%2Bsyb9UC9bHtUaaKtfMAtwwhMuvEdH32X7Q0QgOqeZ4W9vI31jskg8CoXQHelrevc0A%3D%3D%7Ctkp%3ABk9SR8ivy-j5YA
It is a Cisco Catalyst power supply
Cisco Catalyst 6504-E 2700W AC Power Supply PWR-2700-AC/4 AA23420
341-0138-02
I paid under $35 for it post paid and it really does provide 50 VDC at
up to 53 amps when running on 240 volts AC. If you use it on 120
volts, it is good for about 26 amps. It has a rather quiet fan that is
not at all objectional, and is small and light weight.
It is slightly narrower than what fits in a 19" rack, so I made two
ears that will now let it will bolt right in just fine. To activate
the power supply you must ground one of the small pins on the power
plug. I attached a photo that shows how to do it. Looking at the plug,
there are four blade contacts on the left side and two blade terminal
sets on the right. There are four rows of six pins in the middle
between the big terminals. Short the far left pin of row 2 to the 2nd
pin from the left on row #1. This will allow the power supply to
operate. The two blade terminals on the far left are 50- and the next
two sets just to the right of them are the +50 ones.
I just thought this info could be of use to VHFers for solid state PAs.
Dave K1WHS