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A 50,000 watt hollow state AM transmitter

I decommissioned a 317C-1. The cabinets make a great garden shed. Still have a 317C-2 with power too it but it has not made RF in 6 years. Would have to patch it back in. Since I have three solid state back-ups the 317 will most likely not see air time. I can still light up the filaments when I have tours of the site.
 
Was it common to have an oscilloscope as part of a transmitter?
With some, like the RCA Ampliphase, a scope was essential. The key letters in that word are "phase" and anything that has a phase adjustment needs a scope (very simplified explanation... sorry to the engineers here... I used to make lots of extra spending money working on the 10 kw Amplifuzz at a competitor's station 560 AM in Guayaquil when it decided to occupy about 200 kHz of the AM band, including my station at 660. )
 
Radio Marti at their Marathon transmitter site ran two 317s into a combiner to try and get 100 kW to the antenna system. Never did work correctly with a good deal of the power going to the reject load.

There was a transmitter engineer on the ROAD program (Retired On Active Duty) who used to fall asleep during his shift. We'll call him Bob. If one of the transmitters dropped off line, the remaining transmitter dumped 25 kW into the dummy load. A piece of wood lay on top of the dummy load and would start to smoke. Bob would wake up when he smelled the smoke and switch the operating transmitter directly to the phaser, by passing the combiner.

Later on, the system was programmed to sense the single transmitter fail and perform the bypass switch automatically. We called it "Virtual Bob."

The two 317s were replace by a 3DX100 but a single 317 was retained as backup. To my knowledge it is still operating.
 
This one's rotting away in Boise Idaho. Hasn't been on since 2009.
Tested once in 2011. Station was on the air with a kilowatt BE but has been off for about a year.
Had a CKLW asset sticker on it.

1747149974136.jpeg
 
As contrast, here is a 100 kw solid state Nautel next to a 30 kw auxiliary transmitter at Radio 10, Buenos Aires, where I consulted for many years earlier in this century.

1747181565800.png
 
Radio Marti at their Marathon transmitter site ran two 317s into a combiner to try and get 100 kW to the antenna system. Never did work correctly with a good deal of the power going to the reject load.

There was a transmitter engineer on the ROAD program (Retired On Active Duty) who used to fall asleep during his shift. We'll call him Bob. If one of the transmitters dropped off line, the remaining transmitter dumped 25 kW into the dummy load. A piece of wood lay on top of the dummy load and would start to smoke. Bob would wake up when he smelled the smoke and switch the operating transmitter directly to the phaser, by passing the combiner.
It could have dropped to 100 watts. Cuba has over 20 stations, from 1 kw to 100 kw, on 1180 all across the 800 mile wide island and all rebroadcasting one of their national networks. I never understood why they kept it running. For a while, they ran on 540 every Saturday with a huge longwire dragged from a plane!
 
Way back when 1180 Marathon was first turned on I heard it in Boise ID. .
Didn't take Cuba long to "jam" the hell out of it.
Just a grain of sand in Castro's shoe that kept resources from going to better use.
 
Just a grain of sand in Castro's shoe that kept resources from going to better use.
Like killing university professors in front of their wife and family?

Or sending them for free room and board with a side of torture Presidio Modelo on the Isla de Juventud?
 
While Putin was occupied with the Ukraine, why the US allowed Cuba a "free pass" I will never know. The is my bargain: for every square kilometer of the Ukraine you take we take the equal amount of land from Cuba.
 
It could have dropped to 100 watts. Cuba has over 20 stations, from 1 kw to 100 kw, on 1180 all across the 800 mile wide island and all rebroadcasting one of their national networks. I never understood why they kept it running. For a while, they ran on 540 every Saturday with a huge longwire dragged from a plane!
1180 in Cuba was the sole reason I was able to get a 500 watt FM booster for WJNT AM in Mississippi. FCC inspector drove up from New Orleans and we spent a night taking measurements. We determined that Radio Habana Cuba was beaming the equivalent of 200kw towards the US. WJNT-FM1 operated during night time hours only under a STA that was renewed for several years. It finally went away when the current owner applied for a 250 watt FM translator.
 
Like killing university professors in front of their wife and family?

Or sending them for free room and board with a side of torture Presidio Modelo on the Isla de Juventud?
Did that and let people sit in the dark.
Not having to run jammers would make no diff to the people or the oppression.
They'd continue to have poor services.
Those in power would benefit.
 
While Putin was occupied with the Ukraine, why the US allowed Cuba a "free pass" I will never know. The is my bargain: for every square kilometer of the Ukraine you take we take the equal amount of land from Cuba.
What relationship is there between Cuba and the Ukraine?

Keeping this about radio, in the last decade, China has totally rebuilt the AM networks and stations in Cuba and fully created the parallel FM system, totaling around 350 stations.
 
Keeping this about radio, in the last decade, China has totally rebuilt the AM networks and stations in Cuba and fully created the parallel FM system, totaling around 350 stations.
That shows you how well the U.S. embargo is working. What does Cuba need from the U.S. that they can't get from China or Russia?
 
Sorry I wondered off topic and got political. Cuba ignoring the Havana Treaty and the "jamming of signals" is a radio issue. That would not had been an issue had the CIA done their job in the 1960's.
 
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