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Looking for a Low Power AM Transmitter

P

PaulBWalkerJr

Guest
I need a Low Power, Type Accepted, AM transmitter running anywhere between 40 and 60 watts/ My licensed night power is 27 Watts and I do have some line loss.

I don't have alot of money, but if anyone has one they can part with or knows someone who might have one.. email me off-list...

[email protected]
 
The only one That I know if that is Type accepted is by Radio Systems. However I think theirs go up to only 10 watts. We really do need a good supplier of low power AM transmitters that are type accepted and do between 1 and say 50 watts, 1 and 100, and 1-250 watts, just for the purpose you state. Especially if nighttime IBOC is approved, we will need ones that can handle the IBOC input.

There is a nice looking transmitter on TransmittersRus that goes up to 80 watts, and its Digital PLL tuned. The problem is it isn't FCC type certified. Try contacting them. The guy who deals with the Transmitters, Phil DeCadenett is a great guy. www.transmittersrus.com

http://www.transmittersrus.com/tru_rpg20.htm
 
Check with LPB. They make (or used to make) a version of their carrier current and TIS transmitter that is certified for broadcast use. There are a bunch of these out there being used for low power operation at night or for backup use.

http://www.lpbinc.com
 
Unless the rules have changed over there you can use any AM transmitter for night power as it is classed as a secondary transmitter and therefore needs no type approval.

Naturally it needs to meet the necessary technical requirements when in operation.

Some years back I was involved in the purchase of 1050 WLYC in Williamsport, Pa which had gone dark. Part of the rebuild at the TX shack included junking the 60w LPB (pile of junk). I replaced it with a 50w pulse width modulated unit for our 38w night power which was a vast improvement over the LPB both in fidelity and coverage.

Phil
Transmitters 'R' Us
http://www.transmittersrus.com
 
We had a kilowatter on a Mexican claer which got like 35 or 40 Watts PSSA. Thwe transmitter (820D2) was able to run 250 Watts without any problems. The consultant cooked up a resistive divider which dissipated it down to the required level. Worked great and saved us buying another box, for the price of maybe three or four light bulbs in waste energy as heat.
 
Transmitter Man said:
Unless the rules have changed over there you can use any AM transmitter for night power as it is classed as a secondary transmitter and therefore needs no type approval.

Naturally it needs to meet the necessary technical requirements when in operation.

Some years back I was involved in the purchase of 1050 WLYC in Williamsport, Pa which had gone dark. Part of the rebuild at the TX shack included junking the 60w LPB (pile of junk). I replaced it with a 50w pulse width modulated unit for our 38w night power which was a vast improvement over the LPB both in fidelity and coverage.

I heard this very installation. It's sound blew tha main out of the water. a Great sounding transmitter.

Clouseau
 
Are we sure a night transmitter needs no type approval? I was told otherwise by someone else...

Nonetheless, I'm still looking for a 60 Watt LPB type unit... It doesnt matter how it looks or how old it is, as long as it functions...

[email protected]
 
One of the stations that I engineer for uses the LPB-30 for night power and it works very well. Audio is being delivered via an Optimod AM 9200 / Digital.

The only problem I have found is the trimmer that is used to set the power output is a course trimmer and it is "touchy" to get it exactly where you want it. Once you get it there, you have to touch it up from time to time, it won't stay put, and varies just a little. (just a few watts) I wish they had used a 20 turn pot for that adjustment or some sort of power control circuit so it would stay EXACTLY where you put it.

All and all, a decent box. You get what you pay for. 8)
 
I think this rule covers that, but you have to demonstrate the the power level is in tolorence if asked by the inspector and there is no objectionable interf. These things granted on secondary basis, the FCC gives them but can take it away and you are not protected contour at night.

73.99
(k) A PSRA and PSSA does not require compliance with Sec. Sec. 73.45, 73.182 and
73.1560 where the operation might otherwise be considered as technically
substandard. Further, the requirements of paragraphs (a)(5), (b)(2), (c)(2),
and (d)(2) of Sec. 73.1215 concerning the scale ranges of transmission system
indicating instruments are waived for PSRA and PSSA operation except for the
radio frequency ammeters used in determining antenna input power.
 
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