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Therealporkchop
Intermediate Member
Username: Therealporkchop

Post Number: 179
Registered: 11-2002


Posted on Saturday, March 19, 2005 - 5:11 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I just wanted to let you guys know that I finally did this to one of my radios. I am pretty impressed with it too. Now take this for what it is, I know my meter isn't 100% on the money, but look at the differences and tell me what you think. I put the MRF455 instead of the 2SC2290 because it's what I had laying around.

The radio is a Galaxy 33HML. The usual peak and tweak info from this site has been done to it, nothing special. Dead keys were 1 watt low, 4 watts medium and 10 watts high. I installed the final as per the directions. I moved my low key to 2 watts, left the medium key at 4 and moved my high key down to 6-8 watts. Before the modification the radio would swing about 35 watts PEP and 10-12 watts average power. After results are about 80 watts PEP with average power showing about 30-35 watts. Don't get bent out of shape, I know my meter isn't a Bird meter.

I have been talking continually on this radio for three days without one problem. I did add a heat sink to the back of the unit and plan to add a fan also, but heat doesn't seem to be an issue right now. A station about 30 miles or so away tells me that my S report is up 2 S units and I'm louder and clearer now. If you've been thinking of doing this as an experiment, go ahead. I had fun doing it and I think it's trick that this works and works this well even if it lets the blue smoke out on the next key up.

Enjoy!!!
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Patzerozero
Advanced Member
Username: Patzerozero

Post Number: 586
Registered: 7-2004
Posted on Saturday, March 19, 2005 - 11:16 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

you had about 10 watts avg before & it went up to around 35 w avg. so, let's see, double 10 watts to 20, double 20 to 40 or in your case 35 is pretty close. there's your 2 S-units, more or less! if it hasn't blown up in 3 days & heat hasn't been a problem, you should be GOOD!
where'd you get the directions for that mod, porkchop? i've got 'em for old superstar 360, president dx radios & somewhere for cobra AM radios. haven't looked for those mods in years because i haven't done 1 of those mods in a LONG time, been turning 'em down for amps! just modded a texas ranger 296 & have another & may go crazy on it & see what it can do. definitely a candidate for that type of mod.
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Therealporkchop
Intermediate Member
Username: Therealporkchop

Post Number: 181
Registered: 11-2002


Posted on Sunday, March 20, 2005 - 12:32 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I emailed you Pat.

I haven't had a major problem yet. Like I said I know my wattmeter isn't dead on the money, but I think it's a good reference point. Plus the person giving me the S report has the same equipment that they have always had and other than the mod to the radio I am using, everything else is the same too. I think it's a good alternative for guys who drive company trucks and they have a no amp policy. Plus like I've always said, CB is just a hobby and this makes it more interesting.
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Roslintronix
New member
Username: Roslintronix

Post Number: 3
Registered: 3-2005
Posted on Sunday, March 20, 2005 - 4:38 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Therealporkchop, Sounds great! Being a ham operator, I certainly can appreciate your enthusiasum, and like to hear about people experimenting! I'm glad that you (others too) have a desire to try things out! Great job and thanks for helping me believe there's hope for radio yet!!! Ross
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Rob5mike
Intermediate Member
Username: Rob5mike

Post Number: 149
Registered: 7-2002
Posted on Monday, March 21, 2005 - 6:19 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

If you don't mind,could you let me know how this is done? I drive for one of those "NO AMP" companies.
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2600
Advanced Member
Username: 2600

Post Number: 505
Registered: 7-2002
Posted on Tuesday, March 22, 2005 - 12:33 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Er... "Directions"? ? ?

Like, uh, from where?

73
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Therealporkchop
Intermediate Member
Username: Therealporkchop

Post Number: 190
Registered: 11-2002


Posted on Sunday, April 24, 2005 - 2:10 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sorry for the delay, I've been working nights. I have the plans outside in the shack. I too am a HAM operator. I actually know better than to do such to a radio, but you know. My phone line outside is acting up due to rain, so I can't get my computer outside to get online. I'll try to remember to go get it and post it here before I leave for work. I've been working nights and I haven't been here in awhile.

Pat, your email doesn't seem to work. So I haven't forgot you either bud.

PS...this is based on a Galaxy 33HML. You can do it to other Galaxy radios, but you might have to tinker around with the capacitor values to get the power you want. I don't know whether this will work on other radios or not.
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Therealporkchop
Intermediate Member
Username: Therealporkchop

Post Number: 191
Registered: 11-2002


Posted on Sunday, April 24, 2005 - 2:12 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Oh, 2600, I can't say where I got the directions from cause it was from a competitor of this sites...no reason to cause static with a moderator....

Stay tuned........
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Patzerozero
Advanced Member
Username: Patzerozero

Post Number: 717
Registered: 7-2004
Posted on Sunday, April 24, 2005 - 11:49 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hmmmmm....i've received e-mails from others almost everyday since??? anyways, whenever porkchop.
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Therealporkchop
Intermediate Member
Username: Therealporkchop

Post Number: 245
Registered: 11-2002


Posted on Monday, July 11, 2005 - 7:40 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

OK. You've all waited for this, and I finally got my lazy you know what outside to the shack and retrieved this for you.

I did this on a 33HML. You can do it to whatever radio you choose to, but I don't know if SSB radios will accept it or not.

Where you might want to mount the 2SC2290 would be right up under the screw hole in the center of the back for the bottom cover. You might even want to add a heatsink to the back of the radio. You will need 1 2SC2290 final, a ferrite core,100pf Silver Mica capacitor,10 ohm resistor, about 1ft of magnet wire,600pf capacitor. You may even need a 820-1000pf Silver Mica capacitor.

Mount your final in your desired location. Make sure both emitters have a link linking them to the screws that mount the transistor. Basically you are grounding them.

Use 3 ferrite cores, or one large one from an old amp and make 6-10 turns of wire. This will be your power wire from the power input of the radio. You can use 14 gauge or better wire.

From the collector to the left emitter solder the 100pf silver mica capacitor there. Also solder the power filter choke you made with the ferrite core from the collector to the power input on the back of the radio. You might want to tie strap it down or use foam tape to try to keep it from vibrating loose or yanking it from the collector.

Take the 10 ohm resistor and wrap atleast 11 turns of the magnet wire around the resistor. A step I'll include here, that someone else didn't and this didn't work for me the first time, is to solder each loose end of the magnet wire to resistor's lead. One on each end, it won't do it's job if you just wrap the wire around it. Duh..stupid me. Solder one end to the emitter lead and the other to the base lead. This creates a Class C amplification circuit, or so the author of the original plan says.

Remove the tuning slug, L33, and install the 600pf capacitor from the 2SC1969 final feeding the base of the base lead to the base lead of the 2290. Remove all but two rounds of the wire from the L33 slug and then solder one end into the original hole for the L33 inductor and the other end to the collector of the 2290.

You will need to install a ground wire from the emitter lead to the ground input for the radio.

If you experience power drifting, like I did, you may need to change C166 to silver mica capacitor from 820pf to 1000pf. It can effect the tunability of L33. If L33 has to be turned all the way out, you will need to decrease the value of the capacitor that is installed in the original L33 spot going to the base of the 2290. If you have to turn it all the way in, you need to increase that value.

If you would like to try for more RF output, you can change C165 to a 1000pf silver mica capacitor.

That's it. If you do this correctly it'll work. I tried it and it worked for me. At first I did have power drifting and talking on it for long periods of time caused it to drop off on the carrier. You really need to install a heatsink and a fan. I found that if I just turned it down to around 25 watts RMS and about 90-100 PEP, it works fine and I can jibber jabber on it all day long. Plus, it's loud as krap. You can get out with it, you're sure to be heard.

How long will it hold up? I don't know. Is it bad on your radio, I don't know. Was it fun to do it? Yes. Was it worth what I paid for the plans? No. That's why I'm posting it here, to save you guys the money. Any questions email me and I'll try to help you out.
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Xmean_n_nastyx1
New member
Username: Xmean_n_nastyx1

Post Number: 5
Registered: 5-2005
Posted on Sunday, July 31, 2005 - 11:23 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

In the last paragraph you made the most important, and subsiquently, the most generous statement. I just wanted to write you and say thank you for takeing the time and effort,1 to do the mod, but 2 to post it. It means a lot to people like myself, on a limited budget, to know that there are still good, honest generous people out there. To buy, and then GIVE away the plans shows just what kind of person you really are. I probably wont do the mod but i wanted to personally thank you for the opportunity to have the resource if I did want to. Thank you, Mean_N_Nasty
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Sg569
Intermediate Member
Username: Sg569

Post Number: 183
Registered: 12-2004
Posted on Sunday, July 31, 2005 - 2:45 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Xmean,

Not only does he give the plans away, He has been more than happy to answer my ?'s on this mod.

Thank you Therealporkchop, thank you very much.
sg569
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Therealporkchop
Intermediate Member
Username: Therealporkchop

Post Number: 283
Registered: 11-2002


Posted on Sunday, July 31, 2005 - 5:07 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Well you're welcome. I've enjoyed the mod, but I think you'd be time and money ahead if more power is what you are looking for, to just buy an amp.

Going either way there are legal issues to look at, so if you're gonna have a headache, I think you'd be better off just buying a seperate amp.

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