| Author |
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Sixkiller505
| | Posted on Tuesday, March 11, 2003 - 2:02 pm: | 
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can any tech tell me if i can replace a box with 1446's with 2290's since they both carry the same watt rating. and which set will swing more,and take more drive |
Kc0gxz
| | Posted on Tuesday, March 11, 2003 - 11:27 pm: |
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From one of the spect sheets I have, the SD1446s' are rated to be around 60-70 watts and the 2SC2290s' are rated at 80-90 watts. I have learned that the power ratings depend on which vendors' spec sheet you are looking at at the time. To answer your question, the 2290s' are physicaly much larger in size than the 1446s and have an intirely different mounting system. The 2290s' are flanged where the 1446s' are not. However, 2290s and can be interchanged with 2SC2879s and a few others. They are identical except for their power ratings.
Just out of curiousty, why would you want a trade-off like that? The gain wouldn't be enough for anyone on the receiving end to even notice much. You have to more than double your power out-put just to move someones S-meter up one unit. In other words, let's say that you are using 500 watts of power and you're giving someone in the distants 5 S-units. Now, the next day you are using 1000 watts. That same guy on the receiving end might see just one S-unit increase on his meter. At the most, maybe one and a half S-unit increase.
There is nothing wrong with a "box" that has a pair of 1446s in it as long as it is set up correctly. Use a low 1.5 drive and let the radio swing into it. It will work just like a modulator. Loud, loud, loud. What's more important? Being seen on the S-meter or being heard by others. To me, S-units are of little value. Being heard in the distants is. Hope this helped.
Jeff, kc0gxz. |
2600
| | Posted on Wednesday, March 12, 2003 - 1:34 am: |
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The parts that are wrapped around the transistors have to match the type that's in there. The Watt rating alone is only one part of the picture. If you just swap transistors, you will probably see less power than before, until the rest of the amplifier is changed to match the new type number. You will never get enough additional power to pay for the effort, even after doing that.
73 |
Tech671
| | Posted on Wednesday, March 12, 2003 - 5:50 am: |
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Agree with above mostly. 14s are flange just as 22s. Just because the power rating is similar doesn't mean the input and output tuning is. The closest thing in a larger size to a 1446 would be like a srf3749, maybe a 454 or 3800. All are low drive transistors. 2290s do take more drive than 14s but just swapping them in likely you may see a drop in power and some swr changes on input and output (not for the better). |
Sixkiller505
| | Posted on Wednesday, March 12, 2003 - 11:44 am: |
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my thanks to 671/2600/kc0gxz it's not for me!! it's a hardhead friend of mine,who cant keep his hands out of the box.he would not take my word for it!!! but he repects copper techs and forum members imput.i told him the money that he would spend for this venture,he could buy his own computer, and stop looking over my shoulder while iam on the forum.(ha ha ha !!)671 i had to say all of that,did'nt want you to think that one of your homies was that DUMB!! ha! ha! ha! 505 love country |
Crafter
| | Posted on Wednesday, March 12, 2003 - 12:51 pm: |
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If it were me I would leave it alone. |
2600
| | Posted on Thursday, March 13, 2003 - 12:40 am: |
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I tell them it's just economics. If you're simply in love with the idea, then who cares what it costs? Predictions about the results he'll get are wasted, if he JUST HAS to find out for himself.
For most folks, the radio is just a tool. I ask them whether they want "Watts per dollar" or "Dollars per Watt". Just getting a larger amplifier puts you into "Watts per dollar" territory, especially the way linears are priced these days. If they insist on diddling with a WORKING unit, it pretty well guarantees they will spend dollars per watt. This is a pure guarantee if you measure how many ADDITIONAL Watts those dollars got you. It's just a choice, nothing more.
Besides, if he learns it the hard way, maybe the lesson will stick for a while.
73 |
Kc0gxz
| | Posted on Thursday, March 13, 2003 - 3:13 am: |
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2600.
What do you tell them if they have a 250 watt amp and want to move up to a 350. I have trouble getting some customers to understand what it takes to move an S-meter just one S-unit.
Jeff, kc0gxz. |
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