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500w Amp For 95% AM 5%SSB
- Thread starter GreenTeg
- Start date
The 400V or 500v seem right up my alley as far as AB biased amps go.
Recommended Drive Input? 1w? 5w? Or just whatever gains a 1:4 ratio of dk to PEP?
Needed modifications for 11m use? I have two massive computer fans that are ready to install on any amp. Cooling is covered. Location is on a clean and polished granite slab in my car (good grounding base and keeps VERY cool).
It sounds to me after further research that you guys were right after all, and the previous information I had gained was from a poor source regarding CB amplifiers, I apologize.
Lets cap the max amperage for my car at 45 with a 8 gauge wire to a fused distribution block to a 4 gauge wire to the battery. Which amp can I run with this added "cap."
Thanks,
GreenTeg
**PS: Took your advice Rob, couldn't be happier with the antenna wiring.**
Recommended Drive Input? 1w? 5w? Or just whatever gains a 1:4 ratio of dk to PEP?
Needed modifications for 11m use? I have two massive computer fans that are ready to install on any amp. Cooling is covered. Location is on a clean and polished granite slab in my car (good grounding base and keeps VERY cool).
It sounds to me after further research that you guys were right after all, and the previous information I had gained was from a poor source regarding CB amplifiers, I apologize.
Lets cap the max amperage for my car at 45 with a 8 gauge wire to a fused distribution block to a 4 gauge wire to the battery. Which amp can I run with this added "cap."
Thanks,
GreenTeg
**PS: Took your advice Rob, couldn't be happier with the antenna wiring.**
Last edited:
B
BOOTY MONSTER
Guest
according to texas star , with a 20 watt input the 500V will do 500 watts with a 45 amp draw .
the 400 will do 400 watts with a 40 amp draw . both of those amps can do more power than they are rated for , and draw more amperage . but along with that comes signal degration and bleeding on nearby electronics as well as splattering on nearby cb channels . the more you overdrive those transistors the worse it gets .
heres the info from texas star ...
Texas Star Export Feature Chart
youll need an exterrnal power meter to adjust deadkey properly . on AM mode , use the variable on the front of the radio to get the amp to swing about 450ish with your radio . then adjust your radios deadkey to make the amp deadkey %25 of that ammount . doesnt have to be perfect , but get it as close as you cal . you may have to fiddle back and forth with that because some radios pep output will change when you change the deadkey .
Location is on a clean and polished granite slab in my car (good grounding base and keeps VERY cool)."
granite is not an electrical conductor and can not provide any type of electrical or RF ground at all . using the fans is a good idea . id suggest mounting the amp upside down . (fins up) since heat rises and attaching the fans above the fins . i also wouldnt count on the granite providing any type of cooling effect for the amp .
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the 400 will do 400 watts with a 40 amp draw . both of those amps can do more power than they are rated for , and draw more amperage . but along with that comes signal degration and bleeding on nearby electronics as well as splattering on nearby cb channels . the more you overdrive those transistors the worse it gets .
heres the info from texas star ...
Texas Star Export Feature Chart
youll need an exterrnal power meter to adjust deadkey properly . on AM mode , use the variable on the front of the radio to get the amp to swing about 450ish with your radio . then adjust your radios deadkey to make the amp deadkey %25 of that ammount . doesnt have to be perfect , but get it as close as you cal . you may have to fiddle back and forth with that because some radios pep output will change when you change the deadkey .
Location is on a clean and polished granite slab in my car (good grounding base and keeps VERY cool)."
granite is not an electrical conductor and can not provide any type of electrical or RF ground at all . using the fans is a good idea . id suggest mounting the amp upside down . (fins up) since heat rises and attaching the fans above the fins . i also wouldnt count on the granite providing any type of cooling effect for the amp .
(img)
Booty, when you were referring to the 450w was that for the 500v or the 400v? I would think its the 500v due to the 50w overdrive if it was the 400v.
On the topic of the granite slab, I only meant that it was a good base to put something on that will not flex and is very tolerable to heat. It is quite difficult to heat up a piece of granite, but also just as difficult to cool it back down once it is heated. I'll have to weigh the pros and cons on this piece of added hardware to figure out which best suits my needs. I always have my cooling fins (heat sink) facing up with the fan sucking air away, good point though.
If I cannot run this amp in the same place as the KL-203 currently resides, would it be safe to have it mounted in my trunk in one of the corners? (it is bare/stripped down for weight savings) I should be doing my battery relocation first though and putting the dry cell batt in the passenger corner.
Does the preamp make that large of a difference? I hate when my friend can hear me from 50 (road) miles out but I cannot hear him. It says about 1 S unit or 6db, any other reliable sources for good preamp? I could have sworn there was a 20-30db on some of these units.
PS: Booty, do you use that amp with your equipment on top of it? The small vibrations would tear your stuff apart! Its not the big falls that break electronic, but rather the small pulses that giggle it all to pieces.
Thanks again,
-Greenteg
On the topic of the granite slab, I only meant that it was a good base to put something on that will not flex and is very tolerable to heat. It is quite difficult to heat up a piece of granite, but also just as difficult to cool it back down once it is heated. I'll have to weigh the pros and cons on this piece of added hardware to figure out which best suits my needs. I always have my cooling fins (heat sink) facing up with the fan sucking air away, good point though.
If I cannot run this amp in the same place as the KL-203 currently resides, would it be safe to have it mounted in my trunk in one of the corners? (it is bare/stripped down for weight savings) I should be doing my battery relocation first though and putting the dry cell batt in the passenger corner.
Does the preamp make that large of a difference? I hate when my friend can hear me from 50 (road) miles out but I cannot hear him. It says about 1 S unit or 6db, any other reliable sources for good preamp? I could have sworn there was a 20-30db on some of these units.
PS: Booty, do you use that amp with your equipment on top of it? The small vibrations would tear your stuff apart! Its not the big falls that break electronic, but rather the small pulses that giggle it all to pieces.
Thanks again,
-Greenteg
Many preamps will boost signal more than 1 S-unit. My Icom will boost it anywhere from 4 to 6 S-units. But there is a caveat here. Receive preamps aren't consistent from mfr to mfr; some mfrs make ones that work well and others don't. More often they just increase the noise level too. It is a question of how much noise one gets compared to the signal increase you see. Texas Star preamps -built into their linears- are about as decent as they come.
Yeah, vibrations can tear up electronic gear.
Shock mount them with foam if you can find a way to do it...
Yeah, vibrations can tear up electronic gear.
Shock mount them with foam if you can find a way to do it...
I've already got it on my to-do list over here. The car isn't with me up here at college though, so I'll have to wait another month to get cracking on these projects.
I have foam boards that I use for DJ equipment when I run my laptop, and it is not only great for heat dissipation, but it is cheap to purchase, lasts forever, and of course can take the vibration of a moderately heavily sprung weekend warrior (my car).
When you say the TS amps have a decent pre-amp, you mean like middle of the road, mild noise pick-up, moderate S unit gain?
I think you guys are selling me on this, haha.
-Greenteg
texas star 400 will work great with that radio. i also agree with rob
on getting a skythumper noise cancelling mic .its much louder
on getting a skythumper noise cancelling mic .its much louder
B
BOOTY MONSTER
Guest
"Does the preamp make that large of a difference? I hate when my friend can hear me from 50 (road) miles out but I cannot hear him. It says about 1 S unit or 6db, any other reliable sources for good preamp? I could have sworn there was a 20-30db on some of these units.
PS: Booty, do you use that amp with your equipment on top of it? The small vibrations would tear your stuff apart! Its not the big falls that break electronic, but rather the small pulses that giggle it all to pieces."
the preamp on the 500V i had did boost the signal more than the noise . it wasnt dramatic , but did help some . you should never give the preamp any consideration when buying a CB amp . if it helps consider it a bonus freebie , if it doesnt then no loss .
i put some rubber nonslip feet on the bottom of the 500v (as pictured upside down) to prevent it and the P/S from scratching each other . there was no vibration from the power supply it was sitting on . many texas stars have lasted over a decade in mobile installs and some probally have over a million miles with truckers . i dont think theres anything in the house that could shake or vibrate it more than that ........ unless my big fat azz had fell on top of it . hehehehe
if you mount it in the trunk youll probally want a 50amp or bigger toggle swith in the + power line thats easily reached from inside the vehicle . other wise youll have to go in and out the trunk every time you want to turn it on or off . a trunk doesnt provide the best air circulation for cooling the amp either . youll also have to go to the trunk when switching the amp from AM to SSB mode .
http://www.eham.net/reviews/products/66
PS: Booty, do you use that amp with your equipment on top of it? The small vibrations would tear your stuff apart! Its not the big falls that break electronic, but rather the small pulses that giggle it all to pieces."
the preamp on the 500V i had did boost the signal more than the noise . it wasnt dramatic , but did help some . you should never give the preamp any consideration when buying a CB amp . if it helps consider it a bonus freebie , if it doesnt then no loss .
i put some rubber nonslip feet on the bottom of the 500v (as pictured upside down) to prevent it and the P/S from scratching each other . there was no vibration from the power supply it was sitting on . many texas stars have lasted over a decade in mobile installs and some probally have over a million miles with truckers . i dont think theres anything in the house that could shake or vibrate it more than that ........ unless my big fat azz had fell on top of it . hehehehe
if you mount it in the trunk youll probally want a 50amp or bigger toggle swith in the + power line thats easily reached from inside the vehicle . other wise youll have to go in and out the trunk every time you want to turn it on or off . a trunk doesnt provide the best air circulation for cooling the amp either . youll also have to go to the trunk when switching the amp from AM to SSB mode .
http://www.eham.net/reviews/products/66
Last edited by a moderator:
For what I have found, the 636L mic theoretically works perfect for me (have yet to try it out). I have a very loud voice when I talk, and it is consistent, the only thing I needed was excellent noise cancellation, and that is what the 636 was known for. When I talk on CB, I commonly am using a higher than normal voice just for the added effect it gives my radio (when I tune the mic gain properly, it really makes me sing). I am happy with what I have purchase as far as that goes. Sure the Skythumper or RK56 might be louder, but I wanted crystal clear and punchy audio in my car and this was my decision to keep it that way. I've heard the sound clips on the internet of tests, the 636 definitely fit my style a lot better.
Correct me if I am wrong here, but the 400v and 500v are the same size, right?
Since I have a 90amp alternator, I should be fine with either. That is of course if I can fit them properly in my compact car without losing anything important (seating, cargo room, etc). I just made a few dummy amps (properly dimensioned boxes) of both the 350v size and 400/500v size to test for when I get home. If I cannot fit the 400/500v series though, I will just stick with what I currently have (KL-203).
Go big or go home. Either improve to 450w for another S unit or stay where I am currently. I think even my current setup can become a lot better with proper tuning that I've learned this year at college. Possibly enough even to gain the extra S unit I was looking for and also improve the RX end with the better antenna setups that I have learned (besides positioning, I have a few experiments to run).
Booty, I meant that you have your power supply on top of a subwoofer...haha.
Correct me if I am wrong here, but the 400v and 500v are the same size, right?
Since I have a 90amp alternator, I should be fine with either. That is of course if I can fit them properly in my compact car without losing anything important (seating, cargo room, etc). I just made a few dummy amps (properly dimensioned boxes) of both the 350v size and 400/500v size to test for when I get home. If I cannot fit the 400/500v series though, I will just stick with what I currently have (KL-203).
Go big or go home. Either improve to 450w for another S unit or stay where I am currently. I think even my current setup can become a lot better with proper tuning that I've learned this year at college. Possibly enough even to gain the extra S unit I was looking for and also improve the RX end with the better antenna setups that I have learned (besides positioning, I have a few experiments to run).
Booty, I meant that you have your power supply on top of a subwoofer...haha.
Pre-Amps : RadioActiveRadios.com
This was the preamp I was talking about when I mentioned it earlier.
Any opinions on something like this?
This was the preamp I was talking about when I mentioned it earlier.
Any opinions on something like this?
B
BOOTY MONSTER
Guest
Again, Not a good choice. They are the same preamp that are in the cb amplifiers.
Here are some better choices, BUT in my opinion if this is for mobile, Dont use a preamp. Get the best antenna you can, Wilsons are in my opinion the best all round. And GROUND GROUND GROUND. Ground the radio, amp, antenna, chassis to all electrical componets. That lil money you spend on the ground strap will payoff TONS more than any preamplifier.
Tuners, Preamps, Combiners and Splitters
http://www.eham.net/reviews/detail/3712
HEAR IT Inline Module - GAP Noise Canceling Inline Module
Here are some better choices, BUT in my opinion if this is for mobile, Dont use a preamp. Get the best antenna you can, Wilsons are in my opinion the best all round. And GROUND GROUND GROUND. Ground the radio, amp, antenna, chassis to all electrical componets. That lil money you spend on the ground strap will payoff TONS more than any preamplifier.
Tuners, Preamps, Combiners and Splitters
http://www.eham.net/reviews/detail/3712
HEAR IT Inline Module - GAP Noise Canceling Inline Module
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