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Johnbrowning
Member
Username: Johnbrowning

Post Number: 51
Registered: 9-2006
Posted on Tuesday, October 31, 2006 - 11:30 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Just like the title says. Is their any way to make a Galazy chasis stable on SSB???
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Bruce
Senior Member
Username: Bruce

Post Number: 4147
Registered: 9-2003
Posted on Wednesday, November 01, 2006 - 6:04 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

keep the temp in the room stable .......
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Hollowpoint445
Senior Member
Username: Hollowpoint445

Post Number: 1401
Registered: 6-2004
Posted on Wednesday, November 01, 2006 - 10:18 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Try a crystal with a higher load capacitance than the stock crystal. Generally CB oscillator crystals are 32pf, and the crystal in an export may be lower to allow more clarifier range. You may need to order one from a crystal manufacturer so you get a known load capacitance, and that can be pricey.

Add some parallel capacitance to the crystal so the clarifier and the rest of the oscillator components have less of an effect on the crystal.

Replace all of the oscillator components with components from a more stable radio. The crystal trimmers are especially important, but other components also have an effect.

Crystal oven. If you find one that'll work in a CB let me know! Someone on the forum suggested using a grain of wheat lamp attached to the crystal with a glob of epoxy to stabilize it's temperature. I've never tried it, but it sounds like it could help - especially if you add a thermistor and a circuit to regulate the crystal's temperature.
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Hotwire
Senior Member
Username: Hotwire

Post Number: 1960
Registered: 1-2005


Posted on Wednesday, November 01, 2006 - 10:50 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I agree with Bruce. Don't let it get cold.
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Johnbrowning
Member
Username: Johnbrowning

Post Number: 54
Registered: 9-2006
Posted on Wednesday, November 01, 2006 - 2:57 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Great did I mention that I live in "The Winter Wounderland" "The Great Lakes State" AKA Michigan. It is cold here 6 months out of the year! I wish RCI made the 2950/2970 Chasis with more power like a Galaxy 95T I think it is. I like the idea of 2x2SC2290's for SSB then I would not need a 2 pill amp. The problem is that I need it to be rock solid on SSB and Galaxy cannot give me that and RCI is laking the power I want.I am still considering the Magnum 257 but wish they wouldmake tuneing steps smaller. I guess it does not matter since the RIT comes open from the factory? What I really need is a solid performer like the 2970 in a smaller chasis with more power so an external amp is not needed. It would be nice if they used the 2SC2879 in it instead of the 2SC2290 it will take a much harder SWR spike and survive then the 2290's can take. In a mobil it is always nice to have as much protection as possable. I think that high beta transistors are a bad idea for mobile use but rock when used on a base set up.
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Chad
Senior Member
Username: Chad

Post Number: 1193
Registered: 11-2004


Posted on Thursday, November 02, 2006 - 9:17 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The mangum 257 will do just fine. Mine did quite nicely in the coldest of illinois mornings :-) You may need an amp for the power levels you are looking for. Another thing to consider about high power radios is that those transistors make heat! So actually having the temp rising and falling inside a single chassis is just going to cause further stability problems IMHO. The 257 has presets, can't get much easier than that :-)

Chad
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Johnbrowning
Member
Username: Johnbrowning

Post Number: 58
Registered: 9-2006
Posted on Thursday, November 02, 2006 - 7:44 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Yah I am considering a little amp with 4 MRF 455's in it. I do not talk on AM so I really do not need mega power just enough to talk DX on SSB.The way I figure it this setup will be twice as powerful as anything I ever owned adn will have 4 times more power then my Lincoln.In the past 100 watts did the job just fine for me. I was looking for a 2 pill amp but could not find any two pill amps with SSB delay built in!I thought about a TS400,500 and 667 but I really do not want those chasis's and I really do not need the that much power.
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Perrym1962
Junior Member
Username: Perrym1962

Post Number: 24
Registered: 11-2002
Posted on Thursday, November 02, 2006 - 11:00 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I only use my galaxy mobile for a base radio, but I have found that after about 15 minutes it doesn't drift anymore.
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Wd259
New member
Username: Wd259

Post Number: 1
Registered: 10-2006
Posted on Saturday, November 04, 2006 - 12:43 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

If the drift in only on transmit the freq mod / clarifier jump may be drawing too much current from the 8 volt regulator. If all the time, prb crystal stability as the other gent said. I have a Manum 257 and a 2950, both are rock stable. 73, Dave
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 3346
Registered: 7-2004


Posted on Saturday, November 04, 2006 - 9:46 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hmmmmmmm.....'I wish RCI made the 2950/2970 Chasis with more power like a Galaxy 95T I think it is.'-properly tuned, the 2970 has the same REAL WORLD power as the 95T(real world, anybody can make the wattmeter SHOW 200....).

2 pill with SSB delay & biasing would be a texas star dx 250(2290's & 160 PEP) or dx350(2879's & 240 PEP), or magnaforce 200(2290's & 250+ PEP) or mf350(2879's & 350+ PEP).

the 2950/2970 radios would be a better choice then most any galaxy radio for SSB, 2510/2600/lincoln/emporer would be better yet.

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