Hello, I just purchased a new Palomar Elite 250 amp and thought it was suppose to have the sd1446 transistors in it but mine has the 2SC2290 transistors. Is this better for me or worse. I can only get about 140 watts out of it on high power pushing it with a galaxy dx959 peaked and tuned dead keying 2w and swings 30w. Thanks for any help or info on this. also thinking about selling if anyone is interested will take 100.00 shipped.
-
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.
Palomar Elite 250 transistors
- Thread starter basstracker1970
- Start date
That seems low...you should be seeing 200 watts from a pair of 2290s IIRC? My DX959 (not even peaked) would drive my TS350HDV (2 @ 2879s) to nearly 200 watts with the variable at the lowest setting.
My swr also shoots up to a 3 when I turn the amp on and it's a 1.5 with it off and it's a 1.0 with just radio going to watt meter. Im getting around 140-150 watts max on high power. Is there something wrong with this amp or what.I know when I turn it on the swr shoots up to a 3 and the swr alert start to flicker on my galaxy. is there a fix for the swr problem with this amp. Thanks in advance....
Also forgot to mention the radio will dead key 2w and swing to 30w but when I put the amp inline between the watt meter and radio it will only swing to about 20w. I don't know what the deal is here.
Ok my swr on radio is showing 2.4 swr and on my dosy watt meter is shows a 1.2 swr. I have it hooked up Radio-amp-dosy meter-antenna.
Two things come to mind here.
The first, is that your meter isn't giving an accurate peak reading. A Dosy meter cannot read true peak watts by design; it just gives you AVG watts. The difference is huge. If your amp is seeing a 2.4 SWR into the amp; then not all of the radio's power is getting to the amp. Another thing; 30 watts into this amp is a bit much. More like 20 watts is what it needs. Too many watts in could cause this amp to fail. The best way to figure out how many watts the radio is really doing is to use the radio with a true peak reading meter and then into a dummy load; not a Dosy and antenna.
Second, is that your amp may need to have a different length of jumper between the radio and amp. Experiment with different lengths of radio/amp jumpers until the radio's SWR reads under 1.5. Try a 3 ft then a 6 ft jumper; that is a fair place to start. It is either that, or the amp's tuning caps are out of tolerance or have failed. Also test the radio's SWR reading of the antenna - and then test it against the Dosy SWR reading with a 3 ft jumper. They should be pretty close. If not; I would test them both with a 50 Ohm dummy load and see which one is correct.
Just some thoughts . . .
The first, is that your meter isn't giving an accurate peak reading. A Dosy meter cannot read true peak watts by design; it just gives you AVG watts. The difference is huge. If your amp is seeing a 2.4 SWR into the amp; then not all of the radio's power is getting to the amp. Another thing; 30 watts into this amp is a bit much. More like 20 watts is what it needs. Too many watts in could cause this amp to fail. The best way to figure out how many watts the radio is really doing is to use the radio with a true peak reading meter and then into a dummy load; not a Dosy and antenna.
Second, is that your amp may need to have a different length of jumper between the radio and amp. Experiment with different lengths of radio/amp jumpers until the radio's SWR reads under 1.5. Try a 3 ft then a 6 ft jumper; that is a fair place to start. It is either that, or the amp's tuning caps are out of tolerance or have failed. Also test the radio's SWR reading of the antenna - and then test it against the Dosy SWR reading with a 3 ft jumper. They should be pretty close. If not; I would test them both with a 50 Ohm dummy load and see which one is correct.
Just some thoughts . . .
Last edited:
My dosy meter and themeter read the same swr if i remove the amp out of line radio to meter. I will try the coax length thing. I now have a 3' jumper from radio to amp the a 3' jumper from amp to dosy meter.
Once you add an amplifier you must take SWR readings after the amplifier. You can stop messing with the meter in the radio if the amp is in-line because that will not be your true SWR. Try running the amp on the med power setting and use a 6 foot jumper between the radio and amp.
As far as Palomar amps go the Elite 250 is not bad, the 2290 finals are just fine so don't worry there. Are you running base or mobile? What size wire did you do the feed line with? Is your voltage dropping to the amplifier? Is everything correct with your antenna system? Problems tend to show up when you increase power.
As stated, with some amplifiers you have to try different jumper lengths. This is due to them not being right at 50 ohms. You might also try a better watt meter if you are that concerned about the number you are seeing.
If your getting good on air reports I would just have some fun with it, I'm sure it's working like it should. Don't get too caught up in a number on a watt meter.
As far as Palomar amps go the Elite 250 is not bad, the 2290 finals are just fine so don't worry there. Are you running base or mobile? What size wire did you do the feed line with? Is your voltage dropping to the amplifier? Is everything correct with your antenna system? Problems tend to show up when you increase power.
As stated, with some amplifiers you have to try different jumper lengths. This is due to them not being right at 50 ohms. You might also try a better watt meter if you are that concerned about the number you are seeing.
If your getting good on air reports I would just have some fun with it, I'm sure it's working like it should. Don't get too caught up in a number on a watt meter.
Ok guys I got this figured out and fixed. I added my Low Pass Filter inline right after the radio and before the amp and the swr went down to 1.1 on the radio meter and Im getting much more swing out of radio and the amp now. On high side im dead keying 1 1/2 watts and swinging to 180 watts now. That is fine to me on low side im getting right at 100w and swr is 1.1 with amp on or off now. I guess the low pass filter is taking out all 
the unwanted harmonics that was making my swr go up. My filter is a drake tv-3300 i think.
the unwanted harmonics that was making my swr go up. My filter is a drake tv-3300 i think.
Ok guys I got this figured out and fixed. I added my Low Pass Filter inline right after the radio and before the amp and the swr went down to 1.1 on the radio meter and Im getting much more swing out of radio and the amp now. On high side im dead keying 1 1/2 watts and swinging to 180 watts now. That is fine to me on low side im getting right at 100w and swr is 1.1 with amp on or off now. I guess the low pass filter is taking out all
What that tells me is that there are too many harmonics coming out of the radio. This is caused by having too much/more than 100% modulation. You could change this condition by turning down the mic gain or putting the AM Limiter back into the radio.
Just goes to prove once again that clipping out the AM Limiter is a useless and troublesome mod.
My radio is a Galaxy dx959 and no limiters have been clipped. I just turned up the modulation vr16 and set the hi and low power. I don't clip modulation limiters in my radios that is just crazy. I have gotton radio checks now with my setup and all say im loud with very clean modulation. 73'ssssss
Best bet would be to have a good tech with a scope bench test the radio. Did you buy it new or used? If it was used there are ways to defeat a limiter without clipping it out.
If you bought it new this just once again proves a point. Buy a radio from a place that does great tech work, have it tuned and aligned one time the right way, then be done with it and enjoy.
There is something not right with the radio if you have to run a TVI filter to get it to work right and sound clean. At least you have narrowed the problem down to an out of tune radio, could be a lot worse.
Yes radio is new out of the box.Don't think it's out of tune much if any. I am using a 3' jumper from radio to low pass filter then a 3' jumper from filter to amp then a 3' jumper from amp to dosy meter.