replacement amps for MSF5000 800MHz?

This forum is for discussions regarding System Infrastructure and Related Equipment. This includes but is not limited to repeaters, base stations, consoles, voters, Voice over IP, system design and implementation, and other related topics.

Moderator: Queue Moderator

Post Reply
User avatar
transistor747
Batboard $upporter
Posts: 155
Joined: Wed Jan 26, 2005 2:46 pm

replacement amps for MSF5000 800MHz?

Post by transistor747 »

I have a 15 channel 800MHz SMR, and am looking at replacing the amplifiers used on the 4 control channels...just for giggles.
Has anyone had experience with aftermarket amplifiers in this type of system? It would be nice if they were the same size and mount so they would install in the hole in the cabinet left by the old amp.
Oh yeah, the MSF5K's are 75 watt units.
Thanks,
Sam
"The state of the art may well have exceeded the state of the need"
bernie
Batboard $upporter
Posts: 848
Joined: Wed Nov 07, 2001 4:00 pm

Post by bernie »

My two bits worth:
What is wrong with the MSF amplifier?

I have worked on literally hundreds of these, and I can only recall replacing one transistor module on a 800 meg MSF.

I have spare transistor modules.

I have had some problems with solder on the A+ distribution board, but that was about 15 years ago.

I have one system that only has one control channel, and it has run for years with no problem.
Aloha, Bernie
User avatar
transistor747
Batboard $upporter
Posts: 155
Joined: Wed Jan 26, 2005 2:46 pm

Post by transistor747 »

Hi Bernie,
It's a matter of due diligence. The system is pretty much 100% used by two large industrial clients, and employee safety is a major concern.
They are willing to fund the replacement, for preventative maintenance purposes.
Who am I to argue?
Thanks for your input however, I agree that the MSF is one of the best products /\/\ ever sent out of the factory.
Sam
"The state of the art may well have exceeded the state of the need"
User avatar
xmo
Moderator
Posts: 2549
Joined: Fri Oct 12, 2001 4:00 pm

Post by xmo »

I'm with bernie on this one. Those big MSF amps are virtually bullet-proof.

I can't think of any aftermarket amplifier that brand new out of the box would be as trust-worthy as a 10 year old MSF PA.
User avatar
transistor747
Batboard $upporter
Posts: 155
Joined: Wed Jan 26, 2005 2:46 pm

Post by transistor747 »

Duely Noted, thanks guys.

To go a little deeper, the MSF system is a backup system, the primary system was converted to Quantars a couple of years ago, and the MSF units moved to another location to serve as backups.
Any comments about Quantar amps?
"The state of the art may well have exceeded the state of the need"
User avatar
xmo
Moderator
Posts: 2549
Joined: Fri Oct 12, 2001 4:00 pm

Post by xmo »

Quantar PA's are a different story. Not as reliable as MSF PA's.

They cost a lot to replace. They aren't really field repairable. The depot exchange and flat rate repair charges are pretty stiff. And, since the PA is a smart component that is integrated into the station diagnostics it probably isn't an easy matter to substitute an aftermarket replacement.

We had a discussion here some time back about the issue of the Quantar PA reliability. It seems that on lightly loaded channels they almost never fail. Also, when used on a continuously keyed control channel, they almost never fail. The ones that seem to give the most trouble are on channels that get heavy loading at some times of the day.

The theory is that they heat up under traffic and then cool down - the constant heating and cooling takes its toll and eventually the amp fails.

Some users have chosen to leave the stations keyed with local PTT all the time. The trunking controller ignores that local PTT condition and the PA stays hot all the time - maybe extending the time between repairs [but using more of your AC power!]
800mhz radio
Posts: 8
Joined: Sun Jan 05, 2003 12:16 pm

amps

Post by 800mhz radio »

How many msf5k pa do you need also how many quantar pa and other parts could you use have lots of them on hand let me know will make you a sweet deal on what you need!
Post Reply

Return to “Base Stations, Repeaters, General Infrastructure”