-
You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
I want the straight Scoop!
- Thread starter dieselburner
- Start date
It is mostly about hype in advertising.
Sure you have 1200 watts.
It is in a mobile so you are limited by your antenna system.
If you like watching the meter swing in that thing then you are happy with what you have.
Does not mean all the other operators trying to run a clean station and not interfere with others or disrupt the band appreciate all that splatter that is coming from that amp.
Sure you have 1200 watts.
It is in a mobile so you are limited by your antenna system.
If you like watching the meter swing in that thing then you are happy with what you have.
Does not mean all the other operators trying to run a clean station and not interfere with others or disrupt the band appreciate all that splatter that is coming from that amp.
Yep,not only interfering with other people on 11mtrs,i have some around me on 28am eating up 10mtrs on 28.380usb/lsb/am/fm/cw...its a harmonic of ch28am...so you have to think of that...73 de JW
do it all the time on 10/12 mtrs mbl,really ticks some bases on 10 and 12mtrs when a 250 wtt mbl will out talk there beverage antennas...i run a really good qulity antenna on 10mtrs and run a rci2950dx and tuner...i dont run a cheapy antenna,your station is 99 percent of your coax and antenna,73 de n0zna
I routinely work into Europe, South America, Japan and all of the US on 17, 20 and 40 meters running less then 100 watts mobile. Running an Icom 706MKIIG and a High Sierra Sidekick screwdriver antenna. Power helps but as has been said it's all about the antenna.
Straight scoop?
Hmmmm . . .
If the amp DK's at 250w; then 1000w PEP would be ideal. That also means that you would be drawing less amperage away from your system and won't have as much voltage drop either. Soooo; keeping the amp driven with just enough power to get 1000w PEP would save 25 amps and perhaps .4v drop instead of a .6v drop.
Or do you think that losing 200w at the top is not worth it? That 200w is pretty all crap watts anyway. Those eight 2879's should do 125w/apiece @ 14.2v fairly clean too - which is right in the ball park. No one will ever be able to tell the difference between 1000w and 1200w a thousand miles away anyway.
Straight enough?
Hmmmm . . .
If the amp DK's at 250w; then 1000w PEP would be ideal. That also means that you would be drawing less amperage away from your system and won't have as much voltage drop either. Soooo; keeping the amp driven with just enough power to get 1000w PEP would save 25 amps and perhaps .4v drop instead of a .6v drop.
Or do you think that losing 200w at the top is not worth it? That 200w is pretty all crap watts anyway. Those eight 2879's should do 125w/apiece @ 14.2v fairly clean too - which is right in the ball park. No one will ever be able to tell the difference between 1000w and 1200w a thousand miles away anyway.
Straight enough?
Last edited:
I agree with what you have said IFFFFF....... the only reason for the loss of wattage is lack of drive. If it's due to a LOSS OF AMPERAGE then no, that's not good. You cannot starve an amp to keep it in line with the spec sheet output.
Wouldn't starve the amp for supply current; sure didn't say that. Why would you do that? But I would turn down the peak output power in the radio until I saw 1000w PEP through the amp and in the Bird meter. That is what I'm talkin' about. Usually just turning down the AM modulation to 100%/slightly less - will git 'er done . . .
Last edited:
had the same thing here in W.Tn a few months ago,.. sent an e-mail to KC6MFX (Motor Mouth Maul) and it stopped,............. jus sayin<More audio>
OK so I worked the night shift last night and I am tired so I may have missed something but are you saying that 28.380 is a harmonic of ch 28?
Yeah me too . I know all a about inter mod and ordered harmonics and I could see crap like that coming out a jacked up radio from where filtering had maybe been clipped and 2 freq mixing in the amplifier to make a new freq but normally the cause would. Be bleed over wouldn't it?
IMD or in-band spurs for sure but definitely not harmonics. Channel 28 = 27.285 and the nearest harmonic (2'nd) would be at 54.570 MHz. Unfortunately a great number of people refer to any kind of RFI as being caused by harmonics even when the RFI is affecting a non-radio device like computer speakers.
Thanks for the replies. My biggest concern wasn't the total power output but whether or not there was something wrong with the amp. I removed the lid of the amp and it looks perfectly new. I checked each transistor with an ir meter and they all seem to be working evenly. All temps are within a couple degrees of each other under load. After consulting with xforce, I believe that there is a mixture of two problems at work here. First one was already mentioned here which was an insufficient alternator. The second problem is that I am not driving the 2 transistors in the primary drive circuit hard enough. I was told that I need to have at least 10 watts rms modulated to drive the 2290's and my Bird says I am only getting about 5-6 watts average. Currently, I am getting plenty of power out of the amp and am able to make contact with anyone I hear with good signal reports. I even raised a ruckus on channel 6 with this thing so I guess it is being heard. I am using a 10K antenna that is well grounded and body panels are bonded along with 1/0 cables run for power. Have a great weekend.
Double C in CA
Double C in CA