Mod. limiter

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GunSlinger 338
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Mod. limiter

Post by GunSlinger 338 »

when running rack gear into a plactic radio (cobra2000) lets say

is it better to have the limiter cliped and control the audio from the rack gear

or leave the limiter ???????????????????????

when i run my rack gear to my bone stock cobra 2000 ... the audio sounds good from on air reports ,,, just a little low

i cant seem to get the audio up without making it sound like complete crap
:?
any help ???

thanks
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Buckeye Slim
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Post by Buckeye Slim »

prolly the same problem that badwhiskys having. the audio chain in the 2000 isnt wide enough to pass the audio from the rack gear thru the radio.
Buckeye Slim workin this SUBRUBAN (wwpdx-117) base. rci 2990 on a super scanner (soon to be a jo-gunn 4) mobile magnum s-3 with a bounceback 22" comp 10k setup backed up by 2x4 x-force in a 1990 SUBURBAN "If you are electronically challenged this would not be a good starter radio for a new ham"
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Rickety Bones
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Post by Rickety Bones »

if you still looking for answers, let me know, I see that that post was made in 2009

Rick
The information included in this post was acquired from my own personal experience. Please do not use any of my information as absolute. Please ask others, and/or form your own conclusion as their are several ways to " Pluck - A - Duck ". As always, modifications done herein are done at your own risk.

ABGF! ( approved by Goldfinger )
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redlght
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Re: Mod. limiter

Post by redlght »

I did a 2000 hifi rx tx mod and was told i was only 2.5 wide and had mostly highs and mic gain over half makes it fuzzy the washington i did was 5 wide and sounded great to others on air. So whats up with the 2k? thanks for any clues.

2000 is top graph washington is bottom graph, red line is peaks
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Goldfinger
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Re: Mod. limiter

Post by Goldfinger »

Need more info.
What is the green line? Where are you inserting the audio? Which mods did you do?
To me, the red graphs don't look very different.
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redlght
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Re: Mod. limiter

Post by redlght »

i did the mod rx tx for 2000gtl as listed seems low end falls off unless the washington is able to go wider than the 2k green is background audio sample is taken off of inline sampler and fed to computer to graph. What tipped me off was a friend scoped me off his HF rig the washington was a bit over 5 wide the 2k was 2.5 and i think that is it's stock response.
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Goldfinger
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Re: Mod. limiter

Post by Goldfinger »

Looking at your graph, I'm not seeing the low end falling off at all so I'm not sure what you are getting at. If anything, the 2000 is responding lower.
The 2000 and Washington have completely different transmitter chains so you can't expect them to respond the same. There isn't anything "wrong" with the 2000. I have done both radios hundreds of times and I think the 2000 sounds better. Maybe you made a mistake or there might be something wrong with the 2000. Also the values 426 suggested in the mod section is just a suggestion. If you want more lows, make the caps larger.

Try:
C46 Change to 4.7uf mylar/polyester film or non-polarized electrolytic
C101 Change to 3.3uf tantalum 16 to 50 volt
C104 Change to 10uf tantalum 16 to 50 volt
C108 Change to 10uf tantalum 16 to 50 volt

I've been using these larger values for awhile now but I also change C182 to a .01uF to give the transmit more highs to even it out.
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redlght
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Re: Mod. limiter

Post by redlght »

i wil try that setup
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redlght
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Re: Mod. limiter

Post by redlght »

Would it make much of a difference if changing C102 to a 1000pf instead of a 910pf ceramic disc ?
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Goldfinger
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Re: Mod. limiter

Post by Goldfinger »

Not much. C102 is a feedback cap that affects frequency response. I tried many values when I was experimenting and 910 gave the best balance with regular CB mics. Using 1000 pf (.001uF) won't change it much. As with any mod I post, values are "suggested" and can always be changed for experimentation. ;)
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redlght
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Re: Mod. limiter

Post by redlght »

Was just 910's are 3 a piece i can get 1000pf for 8 per 100.
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