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Technical Topics => Equipment => Topic started by: Laidbackdx on February 05, 2024, 2045 UTC

Title: Cre 8900 10 Meter radio
Post by: Laidbackdx on February 05, 2024, 2045 UTC
I would like to connect a rm italy 100 watts linear to this radio Anybody know what input Power is needed to plug the linear
Title: Re: Cre 8900 10 Meter radio
Post by: RobRich on February 06, 2024, 0200 UTC
Probably around 2-3 watts to limit splatter from clipping, though AFAIK and like many other smaller "10m" amps, most of those RMI amps are spec'd at ~5w max.

Quote
This radio is not a big AM swinging radio.  If you lower the deadkey down to 1 watt the radio will only swing to around 5 watts.

Source: https://cbradiomagazine.com/cre-8900-10-meter-ssb-export-radio/

Appears more than sufficient on AM. You *might* get away with an extra watt or few on SSB, but seriously take care. Do not opt for overdriving the amp even if the output falls somewhat short of 100w. More than a few watts into most of these smaller amps and your signal will likely clip into splattering; that is assuming overdriving the MOSFETs or whatever transistors in the amp's output stage do not fail first.

If you do not have a watt meter to measure the radio output, find one, even if it is a loaner from another area operator.

BTW, I assume you are referencing one of the regular RMI models and not the rather expensive MLA100 with selectable filters. If so please put a 30MHz lowpass filter after the amp to limit harmonics. You can often source older Drake, Johnson, or similar 100w (or higher power) 30MHz lowpass (TVI) filters for like $15 to $30 at eBay. Probably even cheaper at a local hamfest.
Title: Re: Cre 8900 10 Meter radio
Post by: bumblefukery on February 16, 2024, 2044 UTC
There is a lot of speculation on CB and you are very wise asking for help.
I also agree that having a meter, not only for forward but reflected power also is a great asset to have. Buy a quality meter and not some chinese shit as you get what you pay for. Its less expensive to buy a better meter than it is to replace equipment.