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Rascal853
Junior Member
Username: Rascal853

Post Number: 13
Registered: 2-2004
Posted on Sunday, March 25, 2007 - 10:57 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

just wondering if anyone knew of anything else i can do to get more than 5 watts out of this radio ive tryed all the usual but 5 is about it if i turn the dead key down to 1.5 then i can get it to swing up to 9 or ten but thats all if i turn it up to 5 then it swings to 9 or 10 any mods to get a little more out of it? thanks rascal853
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Romstar
Junior Member
Username: Romstar

Post Number: 32
Registered: 3-2007
Posted on Monday, March 26, 2007 - 4:35 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sure,

Replace the finals. The instructions are out there.

Romstar
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Hotwire
Senior Member
Username: Hotwire

Post Number: 2193
Registered: 1-2005


Posted on Tuesday, March 27, 2007 - 12:34 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Rascal, I'm still novice at this type of mod and I do not have the exspensive tools needed anyway. Romstar is correct you will want to have the final replaced. Some shops call this the Super Tune or Premium Tune and costs anywhere from 40 bucks to 100 bucks depending on the shop what type radio and what you actually want done to it. For this money you not only get the more powerful final but you get other componets replaced for just an all around better performing radio. You just have to find that good tech and it is ussually done by word of mouth.
I take all my 148's to a good tech that I have known for years. He puts a 1969 final in them and replaces many of the cheap parts found in Cobras today with supieror parts. Depending on how well of a job the tech does the 1969 final will give a Cobra 148 an average of 20 watts PEP. Sometimes a little more on SSB. Find a good tech and keep him on speed dial. Every serious cber needs a good tech!
Kenny
cef491(27.115lsb)
2sf491(27.555usb)
Indiana
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Dale
Advanced Member
Username: Dale

Post Number: 680
Registered: 12-2002
Posted on Wednesday, March 28, 2007 - 5:04 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

personally id leave it at 1.5-2 dk with 9-10 swing on am and should get around 15 or so on ssb
then just get a klv40.same results maybe even
just a hair better.as im no cb tech either replacing finals is a little more than i wanna
get into.also look at the kl-60 not much more
and definately a improvment.probaly a better anyway
dale/a.k.a.hotrod
cef426
cvc#64
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2461
Registered: 9-2004


Posted on Wednesday, March 28, 2007 - 9:36 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

if you want more swing from a low dead key, try this.
pretty simple yet effective.

get a 1N4001 rectifier diode from rad shak.

Lift the end of R228 that connects to TR42. Place the cathode
(banded end) of the diode towards TR42 and solder the other end to the lifted end of R228. Thats it!
good luck,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2463
Registered: 9-2004


Posted on Wednesday, March 28, 2007 - 9:37 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

PS, if you are deadkeying 5 watts, your final and driver transistors are just fine.
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Rascal853
Junior Member
Username: Rascal853

Post Number: 18
Registered: 2-2004
Posted on Friday, March 30, 2007 - 9:27 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

matt thanks for the reply ,,just one question on this 148 the R228 doesnt connect to TR42 but i went to get the diodes today and then whan i was all ready i noticed thatcould it be R193 because that connects to TR42 its a good sized black resistor! thanks again Dennis
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2464
Registered: 9-2004


Posted on Sunday, April 01, 2007 - 10:03 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

sorry,
copied this from another forum.
its R194 that you want.

you can also try removing the resistor completely and replacing it with the diode.
i like leaving the resistor in.

now, i have done the R194 mod myself.
i have not done it with R228, but the tech i got the mod from is very good.
i would try his way and see if you like it.
you wont ruin your radio.
i think it was just a typo on his part.
i think he meant TR47 instead of TR42.

if you look at the schem. you will see that the label for TR42 is right next to TR47 and might have caused this mistake.

either way, i would try it his way first.
then try mine if you dont get the results you want.

best of luck,
do NOT try this with R193!
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Mtn_man_754
Junior Member
Username: Mtn_man_754

Post Number: 13
Registered: 2-2007
Posted on Saturday, April 21, 2007 - 10:21 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

the old 148's and old grants have the 1969 final, stock from the factory ... mine do
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Rascal853
Junior Member
Username: Rascal853

Post Number: 19
Registered: 2-2004
Posted on Sunday, April 22, 2007 - 9:11 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Kid_vicious ,, matt thanks for the info. but before you posted again with the right resistor # i did it to the specs in the firs post and hooked the diode to R193 and to my suprise bad stuff happened!! so now the dead key is kinda fluxuating and little to no mdulation.. so have you any ideas to fixing my problems? thanks Dennis.
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2505
Registered: 9-2004


Posted on Monday, April 23, 2007 - 7:09 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

you need to replace TR 41 with a NTE152 or a 2N6487.
also replace R193 with a 220ohm 1 watt resistor.
you should also go ahead and replace TR42 with a 2SC945 or whatever sub you can find.

if this doesnt cure the problem, you've only spent 6-10 dollars in parts, and have eliminated a big possibility, which should help the tech you send it to figure out the problem faster.

i dont like to recommend one way or the other because you are the only one who can decide if you want to do something yourself or take it to a pro.

i post what info i do because i figure you would rather have the info and not use it than the other way around.

the things ive suggested to try are by no means a guarantee that it will fix the problem.
they are just the most likely culprit parts and wont cost too much to try and fix yourself.

we all gotta learn this stuff somehow!
best of luck to ya,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Rascal853
Junior Member
Username: Rascal853

Post Number: 20
Registered: 2-2004
Posted on Saturday, July 21, 2007 - 1:12 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

well matt,, ive been busy so havent got around to playin with it yet but ill give it a shot and let ya know what happens thanks again

Dennis

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