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Sixtiesmania
Posted on Monday, October 14, 2002 - 10:36 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hi there all,
I have a new kl 500 amp that I hooked up to my magnum 257 and it seemed to be fine, making good contacts and signal reports. I made sure I only put 1.5 watts deadkey into it and the wires are 8 gauge straight to the battery, with a 3 foot jumper coax cable. Yesterday while using this same setup I discovered my signal(modulation especially), was apparently very dirty? When it was running fine it did get fairly warm (the amp that is) and even on setting 1 the signal is still intermittent. Could it be my battery-alternator system can't handle it, even on low amp output setting? I am running the engine as well. The power meter shows it peaks around 420 watts on ssb. What could be causing this modulation problem if the wattage is still ok? Also, it is NOT radio, as when barefoot the radio is crystal clear to other operators, but switch on KL 500 and it sounds BAD! This has just happened, would appreciate any clues to check.
Cheers
Andrew
739 (Aussie in the States!)
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Taz
Posted on Monday, October 14, 2002 - 3:28 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hmmm. what does that radio swing to? and is the limiter clipped?
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Taz
Posted on Monday, October 14, 2002 - 3:29 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

or you blew the front end out from overdrive.
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Tech671
Posted on Monday, October 14, 2002 - 9:12 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sudden distortion... check list...
1. SWR (losing ground resulting in higher swr) 2. Jumpers 3. Reflection between radio and amp when amp is on and keyed 4. Voltage drop at the amp when amp is keyed 5. Amp going into oscillation (due to one of the previous) 6. Bias in amp failing.
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Sixtiesmania
Posted on Tuesday, October 15, 2002 - 3:19 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Okay,
I have tried another amp (Palamor 250) and guess what? Same bloody distortion problem! I rechecked the power leads, swapped jumper leads, etc still the same problem. It must be radio ?? as the radio is the common thing similiar to the amps. It is a Magnum 257 and the power is turned down to 1.5-2.00 watts AM carier and SSB it swings to 12 watts. When amp is not running all reports are that radio is crystal clear mmmmm... Any clues?
Arhhhhhhhhhhhhh!!!!
Cheers
Andrew
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Sixtiesmania
Posted on Tuesday, October 15, 2002 - 9:44 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Okay,
latest development! I tried another transciever in place of the Mag 257 and it worked 100%. mmmm.. so, after discovering amps were fine I looked at radio again. One thing I had on Mag 257 was a fairly long power lead that was coiled on the floor to tidy up the excess cable, and this was going into cigarette lighter socket. I uncoiled the cable and fed it to the back lighter socket and this seemed to improve things considerably. BUT when going past notch 3 of the power output selector switch it seemed to starve for power again. I am running a 45 amp battery in car and it is a 92 model vehicle without Air Conditioning, so not sure about what size alternator it has. Does this give any more clues to problem that still exists to get setup running 100% in my vehicle?
Cheers
Andrew
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Dx431
Posted on Tuesday, October 15, 2002 - 11:15 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Run ALL power and ground leads (radio and amp) straight to battery with 8g wire and fuse all power leads at battery.
Hope this helps.

431
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Tech671
Posted on Tuesday, October 15, 2002 - 9:20 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Some radios are more sensitive to voltage drop. It would be a good idea to run seperate 10ga hot and ground to supply the radio direct from the battery.
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Sixtiesmania
Posted on Thursday, October 17, 2002 - 10:10 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hey all thanks!
I got amp to work with Mag 257 okay. BUT it seems my battery/alternator don't really like it too much past level switch 3!! The battery warning light comes on the consol when keying up past this level!! So thanks all. I appreciate it!
Cheers
Andrew
PS- Do the KL 500 get hot normally? Mine gets pretty warm after 10-15 mins of chatting, let me know.
bye
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Alsworld
Posted on Thursday, October 17, 2002 - 11:59 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sixtiesmania,

from what I know, most will get warm if not hot if talking for any length of time. 10-15 minutes will warm them up. Does it have any air circulation? Air blowing over the heat sink can work wonders.

Also, you can get a larger alternator but I've got to ask...in your post above you said the engine was running. Was that at idle only or driving down the road?
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Jyd
Posted on Thursday, October 17, 2002 - 12:50 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i would put a micro fan inside the amp,hook it to the power switch.it will help,as for the battery if you got room buy a 1200 cranking amp battery.thats what i use.or if you want to go further go with a higher amp alt,the amp will get warmer if it is starving for juice.
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Bigbob
Posted on Thursday, October 17, 2002 - 10:39 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

TEN TO FIFTEEN MINUTES OF CHATTING,MY GAWD,I use my amp not more than 3 mins. at a time.No wonder yours gets hot,MY GAWD!!!
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Sixtiesmania
Posted on Wednesday, November 06, 2002 - 3:47 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hey All,
I am back in USA again and I got my KL 500 to work finally! It was the power to the Mag 257, it needed direct to battery. Also Big Bob, I didn't meant I talked for 15 mins at a time!!! I meant after 15 mins of back & fourth QSOs!! ha ha. I am sure if I did read War and Peace over the air for 15 mins my amp would melt!!
It's good to be back stateside chatting on skip as conditions seem pretty good, BUT my god there are some mentally challenged Jerry Springer rejects out there who wreck it for normal people! I'd rather listen to Mexico chatter with Rogers Beeps than some of these wackos!! Oh well, that's how it goes I supppose eh?
Cheers all
Andrew
739
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Radiodude
Posted on Wednesday, November 06, 2002 - 10:25 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

3 min on an amp? Shoot it takes that long to make a call. If my amp gets warm after an hour then I start to wonder. Only 3 min on an amp? Its not worth the pwr to key it up.
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Bigbob
Posted on Sunday, November 10, 2002 - 6:59 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Radiodude I got to much law to close to me ,with scanners ya know what I mean?

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