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Therealporkchop
Intermediate Member
Username: Therealporkchop
Post Number: 215
Registered: 11-2002
| | Posted on Sunday, June 26, 2005 - 2:10 am: | 
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OK, I got this off the net or somewhere, I don't remember..
The following conversion has been done to a Galaxy 949 with good results. Beware, the following info is NOT for the faint of heart gentlemen. If you are unsure of your capabilities in this arena, remember, there are qualified Techs that can do this. It's always cheaper to pay a tech on something like this than to buy a new radio. That being said... Here's your mod for the 949 or most ANY radio using the EPT-069610Z board.
Step1) Q47 One additional 2SC1969C Final with Isolation hardware.
Step2) A heat sink should be bolted to the rear of the chassis after this conversion.
Step3) D91 - 1N4148 diode.
Step4) C209 - 390pf 5% 50wv mica capacitor.
Step5) C212 - 104uf 5% 50wv ceramic capacitor
Step6) R242 - 22ohm 1/8 watt 5% carbon film resistor
Step7) R243 - 150ohm 1/2 watt 5% carbon film resistor
Step8) L34 - 22uh conformal coated choke
Step9) Q47 - 2SC1969 transistor.
Step10)VR11 - 100 variable potentiometer
AM Modulation Limiter R-276
With this mod done you should see a power modifification for between 30-40 Watts PEP.
This conversion has been done to the Texas Ranger 696F/SSB Base station, The DX-949/DX-959.
Enjoy, and good luck folks.
OK, I done this. I don't get the results they listed. I also done the mod where you change the cap's and all that jazz. So I figured for sure I'd get some good swing and results out of this project. If I run the volts to the radio at around 14 I only get about 6 watts of AVG power and about 25 watts of PEP. If I crank it up to around 16 or 16.5 then I can get about 8 watts AVG power and about 30 watts of PEP. Something is wrong somewhere and I've even experimented with different cap values. Do you need to do a transmitter alignment again once you change all this stuff or what?? |
Bruce
Senior Member
Username: Bruce
Post Number: 2895
Registered: 9-2003
| | Posted on Sunday, June 26, 2005 - 10:47 am: |
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Sounds like you ARE getting about what i would figure .... remember you only can get out the drive + the gain of the outputs and now you have to split the drive. |
Bigbob
Senior Member
Username: Bigbob
Post Number: 2008
Registered: 12-2001
| | Posted on Sunday, June 26, 2005 - 4:00 pm: |
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Gosh bruce,I guess we need to go to db gain 101,sounds like he needs to increase the bias on the driver to ab2,boy-howdy then that meter will jump,hooooe! |
Therealporkchop
Intermediate Member
Username: Therealporkchop
Post Number: 216
Registered: 11-2002
| | Posted on Monday, June 27, 2005 - 11:33 pm: |
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The bias adjustment pot, I have cranked it both ways, and I see no change. I have rechecked everything and I came to the conclusion that by doing this, you leave one important thing out. The new final you install, the center leg doesn't go to anything...It doesn't follow the output of the factory final??
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Therealporkchop
Intermediate Member
Username: Therealporkchop
Post Number: 221
Registered: 11-2002
| | Posted on Wednesday, June 29, 2005 - 1:28 am: |
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OK, I got the schematics for another radio that uses this same main PCB. On this schematic it shows dual finals. I've followed everything down to a T and even changed the TX Pre-Driver. I can't recall the number of the pre-driver I changed to, I just kept experimenting until I got one that I actually saw a change with. I actually ended up with only about 1 or 1 1/2 more AVG watts and about 3-5 more watts PEP. WOOOWEEE big change huh?
I've got this board layed out just like the schematic for the dual final/higher powered radio. I can't get an increase. I get about 7 watts AVG and about 25 watts PEP max. There is something that Galaxy/Ranger has put into these radios that is really choking them up bad. Does anyone know what it is, what am I overlooking? |
Twowatt
Junior Member
Username: Twowatt
Post Number: 28
Registered: 7-2005
| | Posted on Saturday, July 16, 2005 - 12:44 am: |
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porkchop,
looking at both schematics (single final, dual finals), are ALL of the part's values from the final(s) to the so-239 exactly the same?
do u have a scope?
regards |
Fusebreaker
Member
Username: Fusebreaker
Post Number: 79
Registered: 3-2004
| | Posted on Tuesday, August 16, 2005 - 2:46 am: |
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i thought about doing that to the dx-959 i had for more ssb power.I bet it kicks but on ssb. |
Therealporkchop
Intermediate Member
Username: Therealporkchop
Post Number: 334
Registered: 11-2002
| | Posted on Tuesday, August 16, 2005 - 1:44 pm: |
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You know, I only looked at the schematic for the 959 I believe. I honestly don't remember. But I added the parts in that were in line for the other final. I would assume you would need to change other pieces though. I didn't and I only saw a small increase in power. I do have a scope, but I can't tell you anything about the radio now, I sold it.
Some guy heard the before and after of it, and nagged me until I sold it to him. So it's gone now. But something must have been right, cause everyone that heard it wanted it.
Think I'll buy another one to tinker with and see. |
Twowatt
Member
Username: Twowatt
Post Number: 62
Registered: 7-2005
| | Posted on Wednesday, August 17, 2005 - 3:32 pm: |
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first of all, the center leg (collector) of the NEW final MUST be connected to the same electrical point as the original final - otherwise no voltage and of course no output (from the new final).
secondly, u will HAVE to modify the driver circuit (and possibly the pre-driver) to get more output to the now 2 finals.
assuming the driver is a 2166 {if not change to 1306 or 2166 with high hfe}, changing the cap from the driver's collector to the finals' bases will probably have to be done (Xc= 1/ (2)(pi)(f)(c), to find the cap's resistive reactance - and then reduce accordingly). also, if there is a low ohm resistor between the driver's collector and finals' bases, change to 1/2 present value (or ~ 1/4 if modifying for super modulation).
using a scope is a must for t/s these situations. |
Therealporkchop
Intermediate Member
Username: Therealporkchop
Post Number: 342
Registered: 11-2002
| | Posted on Thursday, August 18, 2005 - 12:01 am: |
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Following the schematic, I installed a jumper to feed the collector, so yes, it's hooked up. I did change the pre-driver and most of the caps in the final RF stages... |
Bigbob
Senior Member
Username: Bigbob
Post Number: 2148
Registered: 12-2001
| | Posted on Sunday, August 21, 2005 - 11:43 am: |
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Having a matched pair of transistors also helps.Bigbob |
Therealporkchop
Intermediate Member
Username: Therealporkchop
Post Number: 353
Registered: 11-2002
| | Posted on Sunday, August 21, 2005 - 2:30 pm: |
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Oh yeah...totally... |
Fusebreaker
Intermediate Member
Username: Fusebreaker
Post Number: 106
Registered: 3-2004
| | Posted on Tuesday, August 30, 2005 - 11:41 pm: |
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what kinda ssb wattage? |
Therealporkchop
Intermediate Member
Username: Therealporkchop
Post Number: 373
Registered: 11-2002
| | Posted on Wednesday, August 31, 2005 - 5:02 pm: |
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Don't know, I didn't check it and I sold the radio. Sorry. |
