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Bert
Member
Username: Bert

Post Number: 65
Registered: 12-2005
Posted on Saturday, July 15, 2006 - 11:30 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hi All:
I have the above radio, made in the Phillipines in December '92. It's completely stock.
Is this radio worth having mods done on? I would like the clarifier opened, the frequencies expanded and have it peeked a little. I don't want any clipping done though. Does anyone have any recommendations for a good tech? I'd have to send it by courier from Ontario, Canada.
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 3086
Registered: 7-2004


Posted on Saturday, July 15, 2006 - 12:12 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hey, kid vicious, whaddya think? a candidate for some tweaking

bert, that's probably 1 of the best CB's for modding ever made! you can do all you'd like & a whole bunch more to it! search this forum for tons of xmit & rcv mods for the uniden grant xl-ALL the mods will work on your mb8719 version 148 & make it SCREAM!!!
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Milkman21218
Member
Username: Milkman21218

Post Number: 79
Registered: 1-2004
Posted on Saturday, July 15, 2006 - 12:41 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

YES it's Worth it! Go to the MODIFICATION LIST to the left of page.Enter and your Radio you will find that you can do a lot yourself. Your radio will be a SUPER TALKING RADIO in a no time.I think clipping one item is the way to increase modulation on that radio. Or buy a small AMP from COPPERS. Like KL-60 up to 70 watts,about $ 40.00 US.OR get a kl-203 up to 120 watts,about $60.00 US. I use a KL-203 ,and they to a GREAT JOB! You can expand freq. yourself with a CB TUNE MANUAL I think VOL.# 2 is for your radio Copper has this also! I DID MINE IT EASY!
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Bert
Member
Username: Bert

Post Number: 66
Registered: 12-2005
Posted on Saturday, July 15, 2006 - 3:11 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Milkman and Pat; thanks guys. It probably seemed like a pretty lame question but I just needed reassurance.
I'll look into the mods, but may opt to send it to someone else. I've never attempted something like that myself and I don't want to mess anything up...... For increased power, etc. maybe an amp would be the way to go. I've already got a new Galaxy 225.
I'm going to look into the frequency mods though. How steady a hand do you need? :}
Thanks again, I appreciate your help and advice.
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Cdn_superpower
Member
Username: Cdn_superpower

Post Number: 69
Registered: 6-2005


Posted on Saturday, July 15, 2006 - 9:22 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

you need the swing mod with the linearized final mod for real.
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Bc910
Advanced Member
Username: Bc910

Post Number: 742
Registered: 7-2004


Posted on Sunday, July 16, 2006 - 9:13 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Has any one put the erf finals in one yet? What did you see? I just got 2 148s and I FEEL LIKE PLAYIN'!!! :-)
BC
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 1908
Registered: 9-2004
Posted on Monday, July 17, 2006 - 12:24 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hey guys, sorry, been out of town with no net connection.

bert, if you've not done any radio "tweaking" before, i would recommend sending it somewhere.
usually we cant make recommendations on here, and no, copper does not do outside repairs or mods.

the place to send the radio is communications experts. they have "the man" working there who can make that radio perform beautifully.
if this doesnt show up, email me and i'll give you a link.

GREAT radio you have there!
matt
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Bert
Member
Username: Bert

Post Number: 67
Registered: 12-2005
Posted on Monday, July 17, 2006 - 2:33 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks Matt. I'll look into that.
bert
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Fusebreaker
Intermediate Member
Username: Fusebreaker

Post Number: 229
Registered: 3-2004


Posted on Friday, November 10, 2006 - 8:16 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

On the ERF-2030 subject what kinda power are the y getting with them on the 148`s?
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Fusebreaker
Intermediate Member
Username: Fusebreaker

Post Number: 232
Registered: 3-2004


Posted on Saturday, November 18, 2006 - 4:47 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The NPC_rc mod is not worth the trouble do a simple peak and tune and set the deadkey to about 3 watts,set ssb power to 13 or 14 watts max
as lou franklin and i discussed through email swing is pointless 100% modulation is a radio with a 4 watt deadkey swinging to 8 watts that is 100%,at 80% modulation distortion starts to kick in.I guess if you only want to talk a couple miles a swinging radio is ok everyone thinks swing increases the distance of your radio when in fact it does the opposite,In an AM radio the receiver must have a deadkey given to it to detect the signal if all it can detect are the peaks of the other guy it sound like ssb. go for deadkey not swing and i have done the npc-rc mod on a 148 wow what a waste of a great radio.it worked fine on AM but SSB sounded like @$#% and i never could get the thing back the way it was so i tossed it under the drivers side wheel of my 4 wheel drive chevy s10 and smashed it at the car wash and threw it in the dumster.Yes it was a 1992 model.If you must volt the final move TP7 purple wire to 12 volt source and adjust dk to 8 watts and swing to about 13 or 14 you will talk much farther just remember when on ssb cut the mic gain down.
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2275
Registered: 9-2004
Posted on Saturday, November 18, 2006 - 10:33 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

please do not destroy anymore 14gtls.LOL
if you get too frustrated with one, send it to me, and i will send you a radio to smash.
lots and lots of high dollar replacement parts inside these babies.
matt

PS-i have the NPC mod on my 2000gtl, and i get consistent reports that my SSB audio sounds like an HF amateur rig.
i think your problems were elsewhere in the radio.
i do not remove TR24 like they say to do.
i leave it in as well as R131.
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Fusebreaker
Intermediate Member
Username: Fusebreaker

Post Number: 233
Registered: 3-2004


Posted on Sunday, November 19, 2006 - 5:13 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I never remove the tr24 limiter under any circumstance or clip anything it was put in the radio for a reason. just out of couriousity how much SSB power are you guys getting out of the 148gtl`s with a plain old good peak and tune?
my buddy said he is getting about 18 watts PEP which i dont see how when the final is only 16 watts and if he is sqeezing 18 watts woulnd`nt that make the ssb audio sound trashy?
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2284
Registered: 9-2004
Posted on Sunday, November 19, 2006 - 10:58 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

18 watts is not too much to expect from these radios.
it is about the high limit though.
15 to 16 is what i usually see.

i put a 2SC1307 in my 2000gtl and i can get about 22 watts PEP on SSB, but i leave it at about 16 watts.

the way i figure it, all these radios are within three watts of eachother, its trying to push that last three watts out of them that makes them sound bad, whatever number that might be.

if i had a totally stock 148gtl that someone wanted me to make "loud and clear", i would change R131 to a 4.7k, change R114 to a 10k (this increases the frequency responce of your TX audio)
change C172 to a 2200uF 25volt.
change C18 to a 680-1000uF 25 volt.
and change TR41 to a 2N6487.
then give the radio a tune up, and set the dead key at 3 watts, and the SSB power at 15 watts.
they would have a clean radio that will talk with the best of them, always be clear, and they can run with or without a power mic.
the radio would not get hot, and would last forever if not abused with high SWR.
matt
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 3374
Registered: 7-2004


Posted on Monday, November 20, 2006 - 12:00 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

kid vicious(and any of the nearly 100 CEF members who i've talked to on the air)-quick question:

how did my npc-rc modded, final-volted modded, limiter-switched-out-of-the-circuit modded, class 'C'/no SSB delay davemade-powered, on the stock uniden mic GRANT XL 2500 miles away from las vegas on LOWER SIDEBAND of channel 13 sound to you sunday? that is the ONLY way i run that radio, AM or SSB, & have NEVER EVER been told it doesn't sound right. (to anybody thinking it:i will not respond to any oscilloscope statements, so don't bother. SOUND quality to the ear, not a picture is all we're talking about here).

just wondering
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Tech808
Moderator
Username: Tech808

Post Number: 12312
Registered: 8-2002


Posted on Monday, November 20, 2006 - 12:22 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

HMMMMMMMMMMMMMMM,

Well lets see now Pat since I have made contact with you more than probably any other CEF Radio Club Member over the years on and off the Sunday CEF Nets I will give you my OPINION.

I have talked with you with the AMP and WITHOUT the AMP throwing a WHOPPING 2 watts at me during a GIANT PILEUP on the Sunday CEF Nets and still heard you over Others throwing 100 to 500 times more power than your 2 watts and you were CRYSTAL CLEAR so I would have to say your Setup is working at 100%

Lon
Tech808
CEF808
N9CEF
CVC#2
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 3380
Registered: 7-2004


Posted on Monday, November 20, 2006 - 6:19 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

AWWWWW, shucks, lon. if i weren't so darned humble, you'd be makin' me blush . as i said, i'm not too concerned with what my mobile CB station looks like on a scope, as long as it produces intelligable audio to those who hear it. my CB base & amateur equipment is another story, my neighbors' houses being less then 40' from my antenna require restraint & cleanliness. restraint is required in the heavily modded mobile as well. there is lots of room to increase mic gain & radio dead key, which WOULD result in the typical unitelligable CB station. while i hold lou franklin's knowledge in high regard, i beg to differ when it comes to some of the tricks that are not always considered favorable. i am NOT really running all that much power in my mobile. and remember, my mobile antenna is just a shortened 1/4 wave that is merely 6' to the feedpoint. i've been known to 'get out' a little. attention to detail, including ensuring all the little tricks are done effectively, helps. all things being equal, & DX does not neccessarily allow that to be the case, 250 watts of dead key & 1000 watts of swing can be beaten up on 2 ways-500 dead key with ANY amount of swing-even to only 501 watts, or 2000 watts of swing with ANY dead key, even 1 watt. might not always sound good, but swing can overcome carrier.
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2291
Registered: 9-2004
Posted on Tuesday, November 21, 2006 - 12:54 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

well pat, seeing as how your grant XL is modded almost exactly as my 2000gtl is; i had better tell you you sounded good!LOL
just kidding, you sound great.
no one could say that you were not 100% intelligible.

the reason i am scaling back my 2000 is for the same reasons you exercise restraint on the base equipment: neighbors.
i RARELY talk on AM from the base, so i am really not concerened about being "boadacious", just want to run clean.
the mobile will remain an AM audio monster.
matt
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Chad
Senior Member
Username: Chad

Post Number: 1223
Registered: 11-2004


Posted on Tuesday, November 21, 2006 - 8:50 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Pat, You know how to run your rig clean WITHOUT the choke back. Give it to thew average "gotta have it at 11" person and it would probably sound... Umm... Not so good.

Namely because you know what the mic gain knob does. The quality of the operator makes a BIG difference in this arena!

Chad
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Fusebreaker
Intermediate Member
Username: Fusebreaker

Post Number: 264
Registered: 3-2004


Posted on Tuesday, January 23, 2007 - 6:52 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i had a neighbor bypass the mic gain on a clipped cobra 29ltd it was homurous LOL
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Fusebreaker
Intermediate Member
Username: Fusebreaker

Post Number: 265
Registered: 3-2004


Posted on Tuesday, January 23, 2007 - 6:54 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i also had a guy bring me a radio that someone solderd a wire across the cb/pa jack (cobra29) for talkback it made the most god awfull squeal it was redicoulous
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Sparkomatic
Intermediate Member
Username: Sparkomatic

Post Number: 418
Registered: 10-2002
Posted on Saturday, January 27, 2007 - 11:53 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The 148 gtl from that time frame will talk loud and clean with the mod limiters clipped.
Unlocking a clarifier on a radio with no built in frequency counter is a bad idea.
I'm really amused about the myth that clipping the modulation limiters on all radios will cause them to overmodulate........Some radios, not all. The 148 is certainly not one of them.
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Cdn_superpower
Member
Username: Cdn_superpower

Post Number: 73
Registered: 6-2005


Posted on Saturday, March 31, 2007 - 8:05 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hey folks, someone really needs to investigate the npc swing mod thing, I am 100% postive there's supposed to be a resistor on the long trace leading the VR10.
I think it was 1.21k 1/2w, I cant find the mod anymore and cant remember the value but it was crucial for the mod to work properly.
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Teham
Member
Username: Teham

Post Number: 81
Registered: 1-2004
Posted on Sunday, February 06, 2011 - 9:09 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have a 148gtl made in phil in 1989. Works fine except on am. when talking local the receive audio is very distorted. Was told that a cap might be shorted to ground. was told it is c176 but can't find it's location. tony cef 259
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Madclocker
New member
Username: Madclocker

Post Number: 1
Registered: 7-2013
Posted on Tuesday, July 30, 2013 - 9:08 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Reviving an old thread....
I have several 148 and 140gtl radios, and one 148 that will only do 2w on AM and about 9 or 10on ssb AFTER tuneup,
I would like to put a 2sc1307 in place of the driver. Is this do-able?
Any other parts required, or removed, or values changed?
Thanks in advance
Cleadus
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Truck_driver_tom1
New member
Username: Truck_driver_tom1

Post Number: 1
Registered: 8-2013
Posted on Sunday, August 11, 2013 - 3:57 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have this 148 made in China. I need to know which way do you turn VR5 to max out the modulation? TIA
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Rockin_horse
New member
Username: Rockin_horse

Post Number: 1
Registered: 4-2014
Posted on Sunday, April 27, 2014 - 9:03 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

How do you determine where and when your 148 was made?
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Dale
Senior Member
Username: Dale

Post Number: 2068
Registered: 12-2002
Posted on Monday, April 28, 2014 - 9:11 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

truck driver just turn it 1 way if you lose audio
ya went wrong way. go other way. when it stops
its maxed DONT FORCE IT. use a plastic screw driver
copper has them here
dale/a.k.a.hotrod
cef426
cvc#64
454 [dx numbers]
38lsb

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