duel final galaxy dx44v

[Trainwreck]

I was wondering ( of it can even be done ) how i would go about adding duel finals to my galaxy 44 instead of a single final. I have a galaxy dx33 hp with duels and it does a super job. Just wanting to up the final watts being put out. Thank you for all the info i can get

 

[Robb]

CB Trick has a page that tells you what you need and how to do it.

http://www.cbtricks.com/miscellaneous/fet_papers/ekl/graphics/AN_2030_2c.pdf

You use 3 MOSFET's to do it; two finals and the driver is replaced with a MOSFET too.

 

[Trainwreck]

Duel final dx 44 v

Ok great thanks robb....could i use the erf2030 or the irf510 or just go for the throat and use the irf520's. Thanks again for the info you have been a big help. Thank you very much. Ok just seen download erf 2030' it is

 

[Robb]

You could use the IRF-510's or the better IRF-520N's. Use mica insulators with heat sink compound instead of the ceramic insulators. Get and install a heat sink on the back of the radio across the back of the finals; you will need it now. Make sure it is flush/flat across the surface!

You can also make the companion EN-369FN and EN-369DR devices too:

You may also consider changing out the 2SB754/70 watt voltage regulator in this radio; as it might be strained or even fail due to the high current demand of these MOSFET output devices when you change them over. The 2SB817 is a 100 watt regulator; just don't buy any of the phony ones from China on eBay. Buy from an American dealer and get a genuine Sanyo device. Cost is about $8.

Get rid of the ceramic insulator behind it as well, and get a mica insulator for it. Use decent heat sink compound too. This will transfer far more heat out of the device. You will find this regulator along the right side of the chassis frame.

Hope that helps.

EDIT:

TR41 is a 2SA473; it can be improved by installing a TIP42C in its place. IIRC, it is the audio driver - it will improve AM modulation. You will find it facing the 2SB754 freestanding on the board.

 

[Trainwreck]

Ok one final question .....can the volt reg and audio driver be purchased at a local radio shack or do they need to be ordered from internet? Thanks again robb for all your help

 

[Robb]

Ok one final question .....can the volt reg and audio driver be purchased at a local radio shack or do they need to be ordered from internet? Thanks again robb for all your help

Highly unlikely; doubtful.

Get the rear heat sink directly from Galaxy; made to fit.

 

[Trainwreck]

What happened to steps 15 and 16 or did i miss read something?

 

[9C1Driver]

I was wondering ( of it can even be done ) how i would go about adding duel finals to my galaxy 44 instead of a single final. I have a galaxy dx33 hp with duels and it does a super job. Just wanting to up the final watts being put out. Thank you for all the info i can get

Since you Galaxy 44 is a single 1969 final radio there is a mod to make it dual 1969 finals. You would also add the heat sink on the back so it would be just like a 77,88, & 99.

Converting to mosfets would be something different all together. I would just call it a mosfet mod of some kind. I guess since mosfets are so different the term "dual final" really does not mean what it used to.

 

[Trainwreck]

Ok thanks, i just finished the Ekl duel 2030 mod and cant get anything. No deadkey or forward swing. I have look for pics of a 99,88,or a 77 with no luck to compare the finished radio to mine to see if everything is correct. I am gonna start from the beginning and walk through it again to see if i missed something,any help will be gratefully appreciated. And thank you all

 

[psycho]

I was wondering ( of it can even be done ) how i would go about adding duel finals to my galaxy 44 instead of a single final. I have a galaxy dx33 hp with duels and it does a super job. Just wanting to up the final watts being put out. Thank you for all the info i can get

Leave it a single final radio. A good tuned single final radio will drive a linear amp a bit better....why, I don't know. If you aren't running an amp, the extra watts isn't worth the trouble.

 

[Trainwreck]

Duel final galaxy 44

Well erf 2030 mod is complete. Now to figure out why i have no output , dont know what happened to steps 15 and 16 in the instruction but i am sure it is something to do with changing components to power the finals. If i cant figure it out, the next step is to pull covers off my 33hp and build it that way thanks for all the help

 

[9C1Driver]

Well I hope you get what was a working radio actually working again after all that. These mosfet mod's for old school radio's are not just a simple final swap, that's for sure.

 

[Robb]

These MOSFETs need to have a minimum 'turn on' voltage of ~3.6v +/-.1v before they will work. Don't exceed that voltage. If you didn't have that much voltage on the 'gate' leg of each of the MOSFETs when transmitting; then there will be no output . . .

 

[Robb]

The actual turn-on voltage for the IRF-520 MOSFET is 2v, ~3.6 is the typical voltage used in many radios. Just wanted to point that out.

http://pdf1.alldatasheet.com/datasheet-pdf/view/22389/STMICROELECTRONICS/IRF520.html