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Bc910
Advanced Member
Username: Bc910

Post Number: 743
Registered: 7-2004


Posted on Friday, July 21, 2006 - 12:05 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

OK I just got a (new to me) VIRGIN 148 GTL made in "THE malasia" THAT IS SOOOOO FUNNY!!! :-) Any way I know this isn't the "perfect"148 but it aint bad, still got the mb8719 etc etc. I know in these models they used slightly less quality filters etc....
So my question is, what would it take to get this thing (recieve wise) where an old 148 or grant should be?
And any other tricks please
I am sooo used to the export stuff now I forgot a lot about these...
This is a new project, just for the sake of being a project, here is a list of plans...
Expo kit model L 120 channels 3 bands of 40
echo board just for fun
NPC RC mod
NEW ERF 2030 final!
clarifier WIDE open!!! (where do I get a 10 turn pot now a days?)
meter wil glow red when transmit (like my favorite radios do!!! :-) wink-wink pat...)
Talk back (with on off switch)
2 way switch for power (hi-low)
Re-paint the covers, new bezel, and new CUSTOM face plate to correctly label all the new and replaced pots and switches
Basically when I am done this sould end up being a export grant (kinda)
Like I said this is a project for project sake, please no "why bother" type remarks.
I just need tips on improving recieve and anything else too
Once again it is late, I am tired, I can't spell (sorry for that)
BC
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Bc910
Advanced Member
Username: Bc910

Post Number: 744
Registered: 7-2004


Posted on Saturday, July 22, 2006 - 7:53 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 1912
Registered: 9-2004
Posted on Saturday, July 22, 2006 - 10:42 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hey BC,

here is a link to a thread that lists all the good mods for this radio.
yes, its for a 2000, but its the same radio on the inside. (except that in the 2000, VR12 is the AMC, and in the 148, its VR7)

http://www.copperelectronics.com/cgi-bin/discus4/show.cgi?tpc=34&post=102442#POST102442

and here is a link to the alignment procedure.
its very detailed and makes for good reading even if you're not gonna do the alignment.

http://www.copperelectronics.com/cgi-bin/discus4/show.cgi?tpc=34&post=113535#POST113535

if you need anymore info, feel free to email me.
later,
matt
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Bc910
Advanced Member
Username: Bc910

Post Number: 747
Registered: 7-2004


Posted on Sunday, July 30, 2006 - 7:09 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

OK thanks everyone for the info, heres what I have done so far...
Expo kit installed
npc/rc mod
internal talk back
hi/lo switch (1 watt carrier/5 watt)
moved the mic gain to the former swr cal location to make room for echo controlls
installed echo, will rip it out the second my new turbo board comes...

I forgot to order the companion transistor with the 2030s whe I ordered them, so the companions are coming with the turbo board...

changed the 5 pin mic from 5 to 4 (I hate 5 pin mic plugs unless they have a real purpose which this doesn't
The new face plate is on order. The new face will have all the correct new locations etc
Also a new bezel, and knobs are comeing too!
Thats it for now
BC
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Wankle
Junior Member
Username: Wankle

Post Number: 23
Registered: 5-2003
Posted on Sunday, July 30, 2006 - 8:32 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

awesome Bc910 , how does the expo kit work? everything on frequency?
let us know how the ERF finals work.
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Bc910
Advanced Member
Username: Bc910

Post Number: 748
Registered: 7-2004


Posted on Sunday, July 30, 2006 - 10:15 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The expo kit works just as expected.
I have never used one before, in the past I always built my own but in this case I couldn't find one of the needed crystals.I get perfect opperati on from channel 16 low bandallthe way up through 40 high band but need to re tune to get those lower freqs, no biggie just havn't done it yet
THe 2030 is in, just with out the companion transistor, so assuming I did everything right, when I get the transistor I should be able to pop it in and it should peak any where from 30 to 40 watts pep (I'm thinking closer to 40)
The whole thing is a mess right now, there is no wire ties left in it, all the knobs, the case, and the bezel are off also the mic jack is still out so I cn solder the new echo board in when it comes (hopefully tomarrow) remainders of the AB-1 board are still in the radio from when I pulled (yanked actually, hard too) it out, but audio is LOUD, power with 1969 is at 20 wats pep into my MFJ-267 swinging from 1 watt or 5!
I also have a ultra bright red/white led on order to replace the meters back light and it will be wired in through the exsisting rx/tx light to glow white in rx and red in tx!
BC
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 1926
Registered: 9-2004
Posted on Sunday, July 30, 2006 - 9:21 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hey bc,
how is that expo kit working for you on SSB?
ive heard that they tend to make the freq. warble on SSBTX because of crystal drift.

also, i have not found anyone that has done the ERF2030 mod to the old style 148gtl. from what i understand, the transmit section of the new style with the front mounted mic jack is a bit different from the old style.
ive been asking around on forums for months now trying to get someone who's done it to get back to me with no luck.
you might pick pat's brain on this one. i think he's the one who told me that the final sections aren't quite the same.

so, im interested to hear your results, as i have an old 148 that i might mod like this too.

later,
matt
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Bc910
Advanced Member
Username: Bc910

Post Number: 749
Registered: 7-2004


Posted on Monday, July 31, 2006 - 7:42 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

OK I am going to attempt a clarifier mod that I havn't done yet here is the mod

If you do the changes below you will get -6kHz to +6kHz with 0 right in the middle.
The Tx will track exactly with the Rx (confirmed on recently calibrated IFR1200S).

1. jumper R175
2. jumper D51
3. remove R149
4. remove R188
5. remove R44
6. remove the wire from the high side (+ or full cw pos) of the clarifier
7. connect pin3 of IC4 to the high side of the clarifier
8. replace R174 with a 3k3 value
9. attach a 12k resistor from the jumper of D51 to pin3 of IC4

PRoblem is my eyes arent working I can't find any of the resistors or diodes etc...
Please help me find
r175
d51
r149
r188
r44
and which one is ic4? I see no markings on the board by 2 ics the others are marked ic1, ic2, ic3, ic5 there are two on the mic side one in front and one in back obviousely ic4 and ic5 but which is which
Thanks
BC
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Hootyal
Intermediate Member
Username: Hootyal

Post Number: 160
Registered: 9-2002
Posted on Monday, July 31, 2006 - 3:21 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hey Bc I have a 1996 model from "The Malaysia" also...that is funny...allot of the parts you are looking for are close together...with the controls facing you find vr5 almost in the middle of the board (bottom near controls)follow straight up past the x3 crystal just to the right you will find r44,d51,r174 ...still looking for the others...I'll type back when eyes are uncrossed hehe!!
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Bc910
Advanced Member
Username: Bc910

Post Number: 751
Registered: 7-2004


Posted on Monday, July 31, 2006 - 3:40 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks bud! I found all trhee. That's my problem too eyes get crossed quick any more
BC
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Hootyal
Intermediate Member
Username: Hootyal

Post Number: 161
Registered: 9-2002
Posted on Monday, July 31, 2006 - 4:10 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

With radio in same position find mic plug on right...follow up 2 inches then back left 1 inch see r243/r175....I'm ascared that r188 is under the hot glue gooo...IC4 is the smaller chip closest to the mic plug (mb3756)...hope this helped. Hooty
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Bc910
Advanced Member
Username: Bc910

Post Number: 753
Registered: 7-2004


Posted on Monday, July 31, 2006 - 6:55 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

OK! I FOUND R188!!
It's in the very front of the board in the center!
Of course I find it after removing asll the wax!
Oh well.
Thanks for all your help Hootyal!
BC
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 1931
Registered: 9-2004
Posted on Monday, July 31, 2006 - 7:00 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hey BC, dont connect to pin 3 of IC 4 (mb3756).
this pin was never meant to have a current draw on it.
much better to go to pin 1.

also, NTE makes 10 turn pots, and they work great.
i highly suggest getting one.
you will have to drill out the inside of the knob to fit though.

ive heard of that clarifier mod before, but i dont know anyone that's done one.
it seems right though.

here's a quick way to get your radio to cover all the channels.
remove or clip R95. right between the PLL and the VCO chips.
this will broadband the VCO. (may have to adjust L19 slightly)
matt
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Bc910
Advanced Member
Username: Bc910

Post Number: 754
Registered: 7-2004


Posted on Monday, July 31, 2006 - 7:40 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks for all the help guys!
Im confused on one last thing though
When they say
"8. replace R174 with a 3k3 value" do they mean 3kohm or does 3k3 mean something else am I missing something?
Thanks again...
BC
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 1934
Registered: 9-2004
Posted on Monday, July 31, 2006 - 9:00 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

they mean 3.3K ohms.

matt
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Bc910
Advanced Member
Username: Bc910

Post Number: 757
Registered: 7-2004


Posted on Thursday, August 03, 2006 - 9:20 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks again every one for the help, but I need one more thing...
The slider mod works great by the way (thanks kid)
But does any one know how I might increse the range to 10-11 khz so I can go to "A" channels?
Thanks
BC
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Bc910
Advanced Member
Username: Bc910

Post Number: 758
Registered: 7-2004


Posted on Friday, August 04, 2006 - 10:39 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 1947
Registered: 9-2004
Posted on Saturday, August 05, 2006 - 12:59 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

well, you might get there by adding a 10uH choke to the banded end of varactor diode, D35.

if you got the mod you did from the defpom site, try doing the one above it, it will have less upslide but downslide should be increased to 10khz+.
look at the mods for the grant XL, and you will find a 10khz switch mod.
if you did this, the +-6khz slide you have would be fine.
also, i used a 10 turn pot, and i dont know, but just using it seemed to increase the slide.
i get 17 khz of slide, 3 up and 14 down.
works for me.
good luck,
matt
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Bc910
Advanced Member
Username: Bc910

Post Number: 759
Registered: 7-2004


Posted on Sunday, August 06, 2006 - 12:20 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

This new 148 project has realy tought me something...
MY EYE SIGHT IS NOT GOOD ANY MORE!!!
Plwease help, where us D35?
Thanks
BC
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 1956
Registered: 9-2004
Posted on Sunday, August 06, 2006 - 11:04 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

if you are looking at the radio from above with the component side facing you, and the knobs pointing at your stomach; D35 will be just to the right of the PLL chip, just to the rear of the 11.325 crystal. (or wires if you have the expo kit installed)
should be a reddish diode with a yellow or green band on one end.
im pretty darn sure that it points toward the front and back of the radio.
its very near all the parts you had to modify for the clarifier mod.
good luck,
matt
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Yankee
Senior Member
Username: Yankee

Post Number: 1271
Registered: 7-2003


Posted on Monday, August 07, 2006 - 1:32 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Both my Uniden Grant XL and Cobra 148 GTL have the 10 KHz. up or down mod, working with grounding or adding power to pin 16 of the PLL. It's a very simple mod. using a 4.7K ohm resistor and a single pole double throw center off mini toggle switch. If interested, I'll post how it's done.
73, Carl CEF-357
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Vanillagorilla
Advanced Member
Username: Vanillagorilla

Post Number: 750
Registered: 4-2005


Posted on Wednesday, August 09, 2006 - 3:20 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Yep...please..post how its done :-)
I have NO need to add channels to my Grant anymore but a 10k switch could be nice!

Hank
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 1967
Registered: 9-2004
Posted on Wednesday, August 09, 2006 - 11:15 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

im not sure this is the only way, but to get 10khz down, you just get an SPST switch and put one side to pin 16, and the other side to PC board ground. (pin 18)
this doesnt work on all channels.

the best way i think is to do the normal slide mod, and use a 10 turn pot.
this should get you about 11 to 12 khz down, and 3 to 4khz up.
good luck,
matt

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