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Bigbob
| | Posted on Sunday, December 07, 2003 - 10:28 pm: | 
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Capable of 70 amps continuous 120 in 16 or 17 out I know this would be a BIG HONKIN piece of iron but I got a christmas bonus coming up and I'm tired of my boomer drawin the power down past 10 volts with my 40 amper,makes the pass transistors hot and not good for the amp. |
Hornet168ky
| | Posted on Wednesday, December 10, 2003 - 1:30 am: |
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http://cgi.aol.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3064721536&category=48708
I just saw this on E-bay Bigbob might help I don't know tho.
Hornet168Ky
CEF#219
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Ca346
| | Posted on Wednesday, December 10, 2003 - 7:10 pm: |
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Here you go BigBob. All it takes is money and 220Volts:
"http://www.wattsunlimited.com/"
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Bigbob
| | Posted on Thursday, December 11, 2003 - 6:31 pm: |
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thanks guys,but a transformer is alot cheaper,just where to find them,uh,could yous loan me 300$ for the 75 amp? |
Ss8541
| | Posted on Friday, December 12, 2003 - 12:37 am: |
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bigbob,
i hope you realize that a transformer is not the answer to your problem. the input and output of the transformer is ac. you will have to rectified the output to dc and then filter it. and it will also not be regulated unless you make it regulated. sounds like you are looking to undertake a project that companies like astron, tripp lite, and pyramid have already perfected. |
Bigbob
| | Posted on Friday, December 12, 2003 - 10:10 pm: |
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Ss8541:I have a home-brew power supply with 80db ripple rejection,crow-bar over voltage protected,and 14gauge circuit connections throughout except at output studs(8gauge),the transformer feeding it is rated 35 amps continuous at 13.8 volts,I figured a 70 to 100 amp trans. would be the ticket but another company sells a fully regulated 70 amp(continuous) p.s. for 289$ out the door.Bigbob |
Bigbob
| | Posted on Friday, December 12, 2003 - 10:18 pm: |
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Ss8541:I can get a quantity of say a dozen or less 40 amp battery charger transformers at 1$ per amp BRAND NEW,can you run 2 or more of these in parallel to double or triple the amps out,I realize I would have to shield them or space them apart to avoid mutual inductance.Bigbob |
Bigbob
| | Posted on Sunday, December 14, 2003 - 6:32 am: |
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SS8541...HELLOOOooo? |
Ss8541
| | Posted on Sunday, December 14, 2003 - 4:43 pm: |
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bigbob,
i think you are saying that you want to replace the transformer in your 35amp p.s. with a 70amp transformer. that will not do you any good if it is regulated for current. once it pulls more than 35amps it will begin to cut itself back. a 1000amp transformer will not change this. only changing the current 'sampler' circuit will change this. i do it with astron power supplies all the time. there is one resistor whos value you reduce to give the p.s. a higher current output. i usually only do this for p.s. that will be used with ssb txers/amps. the reason is that even though the amp can put out more amps, the continuous duty level has not really changed because the heatsink and other parts have not been changed.
for you, i would recommend going with the 70amp continuous duty amp. the main reason is becuase you are planning to use some 'heavy' equipment with that amp that costs some 'heavy' money. you want to run the smallest chance of something going bad and ruining this equipment. a commercial p.s. is your best bet.
as for the battery charger transformers, you can use them, but they put out pulsed dc. that is if you are talking about the charger as a whole. it still has to be filtered, and is not regulated. if you are talking about only the transformer, it is not rectified, not filtered, and not regulated, which brings us back to the commercial p.supplies.
bigbob, when i need a power supply, i let astron handle it. i don't see any need in building something that someone else has already perfected. if you were to build one to meet the standards of the commercial p.supplies, it would cost you more than if you bought one. |
Bigbob
| | Posted on Sunday, December 14, 2003 - 5:12 pm: |
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Think I found my problem,did some audio tests,the radios rf drive was up to high set it to 20 watts ssb now amp wattage and P.S.amperage is back to normal,I really think my P.S. is holding this amp back with more juice this amp may hit a 600 watt peak,do ya think?(boomer400) |
Ss8541
| | Posted on Sunday, December 14, 2003 - 8:34 pm: |
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bigbob,
if it could produce 600w it wouldn't be called the boomer -400-. |
Bigbob
| | Posted on Sunday, December 14, 2003 - 9:33 pm: |
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Yeah,you're right about the boomer,the homemade P.S. is not current limmitted,just voltage(3 scr's in parallel with the turn on leg hooked to a 15 volt zener),the only current limmiting is 2 20amp fuses in parallel at the output,it has 5 mj2955 pnp pass transistors and a 317t voltage regulator a 47000mfd filter cap and a dual input/dual output transformer,I believe the bases of the pass trans' are wired to the input of the 317t,I can't find my schematic right now to be sure.I have very big hands but using little tools,I put all but the transformer inside a 4 1/2 inch square 14 inch long 1/8 inch thick aluminum tube,the transformer is 6x6,the original plans called for 1 pass transistor and a current limmiting transistor,I added 4 more pass trans and deleted the current limmiter,last sunday I wrinkled the 2 fuses but did not pop them.Bigbob |
Bigbob
| | Posted on Saturday, December 20, 2003 - 3:28 pm: |
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Now what the heck is going on?I put the 10-dal head back on the stand in place of the d-104,now everything is back to normal,does the d-104 drive harder than the 10-dal?The d-104 will suck the p.s. down to 9 volts and cut the output to 200,but the 10-dal never pulls it lower than 12 and output is between 400 and 500,could the d-104 be driving the dx2517 into cross-over distortion and causing gobbs of splatter,what do you think Ss8541?I originally changed heads 'cause a ham friend said the d-104 is a better mike for noisy bands,I guess I'll have to turn down the pre-amp on the stand.Bigbob |
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