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Sparky built 100 watt cobra 25.

King Mudduck

FEAR THE DUCK!
May 6, 2005
864
17
28
285 South Western Virgina waving!
I'm thinking of getting one of this for the road but i dont know anything about the guy.Is he a good tech or someone to stay away from? If you dont want to post the answer here for all to see then just IM me. I really need to know before i wast my money!

The reason I'm thinking of getting one of these is because the 387 Pet that i will be driving only has the factory in dash mounting location and there is not enough room their or any where else (that i have seen) to mount a export radio such as a 95T.
 

From what I understand (3rd hand?) it whatever you'd get by tacking something like an RFX-75 on the back end of a '25. Whether that's AVG/RMS/Pep or the infamous 'Bird watts', I have no idea. Why not ask him?
- 'Doc
 
Is that 100W deadkey or 100W fake PEP Watts?
Mike

It's sparky watts (lol) and if you dare to question his claims I'm sure his loyal followers will come running to defend his honor.

To the original question, I wouldn't even think of purchasing a "100 watt Cobra 25".
 
Custom Built Cobra 25 LTD Classic 100 WATTS

It's an RFX-75 add on amplifier that he puts on the back of the radio.

...and yeah it's most likely 100 pep watts.

As far as asking him. People well tell you exactly what you want to hear if they think they can sell you something. I just wanted to know if anyone had heard anything good or bad about his work. I would do the mod myself but i just dont have the time and i'm very picky about who i let work on or who i buy my radios from.
 
$189 for a Cobra 25, and a $25 add-on, OUCH! First off your going to get a few praising his work, and a few condemning it, happens both ways, normal shit for a typical CB shop.

Now, my experience with a "Sparkified":whistle: 148GTL purchased from a forum member here.....

After getting the radio, I immediately noted the Tamper seals which WERE still intact, a quick bench check of the radio using my Tek 485 scope, and a Bird wattmeter revealed results I would expect from a STOCK radio, not bad, but not what I would consider a Professional tune-up.

The radio was well below factory specs on RX, TX was about 5 watts carrier, with about 80% modulation as measured on my Tek 485 Scope.

Breaking the Tamper seals, and a visual inspection of the radio, showed nothing unusual, except for the fact he forgot, or overlooked the heat-sink bolt/nut on the audio chip.

My overview of the radio with the Sparky tune..

The radio performed below factory specs both receive, and transmit. overlooked/forgotten heat-sink mounting hardware. Except for the 5 watt carrier, and tamper seals I would have thought stock radio needing an alignment.


Now, I certainly have no issues with who I bought the radio from, last I knew he still brags about Sparky. The radio sounded fine, receive was not horrible.

I'll leave it up to you to decide, a basic align/tune is NOT rocket science, and can be done by almost anyone with very basic skills. So why were some things overlooked on this radio? No idea, but they were.

The guy may indeed be good, however I was not impressed.


My test bench is good, not great, it lacks some things I would like to have, but this is just a Hobby these days.
 
I think the Spark Man does fine work. I have two 'sparkied' radios.

The price of this Cobra 25 is $189? Woof! Seems a bit high to me. Considering the cost of a decent Cobra 25 and a used 100 watt external amp compared to a Cobra 25 with a RFX in it - It may be cheaper to go with the unmodified Cobra 25 and the external amp. Probably see more watts out of the latter as well...

Cobra 25's are nice radios -BUT- it is just an AM radio. If that is what you want - then; that is fine. For me - I like to see 'the best bang for buck' before I spend a cent...
 
"PEP" is the only true measurement of an amplitude modulated signal" bob85"

But only if you are measuring peak envelope power. Other wise, the other means of measuring power have just as much validity. If you like 'big numbers', using Pep is sure the way to do it. If you don't know what those numbers mean, you really aren't saying anything important or significant at all. What's the difference between about 700 watts Avg/RMS, and 1000 watts Pep? Absolutely nothing.
- 'Doc

(Ask him, he'll say the same thing if he's honest about it.)
 
"PEP" is the only true measurement of an amplitude modulated signal" bob85"

But only if you are measuring peak envelope power. Other wise, the other means of measuring power have just as much validity. If you like 'big numbers', using Pep is sure the way to do it. If you don't know what those numbers mean, you really aren't saying anything important or significant at all. What's the difference between about 700 watts Avg/RMS, and 1000 watts Pep? Absolutely nothing.
- 'Doc

(Ask him, he'll say the same thing if he's honest about it.)


(Ask him, he'll say the same thing if he's honest about it.) I doubt that very much.Seeing as bob is well aware of what AVG power actually means and how it is measured.

There is no such thing as RMS power.

For Amplitude Modulated signals at 100% modulation:

PEP is 2.66 times AVG 100% modulated power or 4 times unmodulated carrier power.

therefore a signal of 1000w PEP would be equivalent to a 250w AVG power unmodulated carrier or a 375 watt AVG 100% modulated signal.

A huge difference between either modulated or unmodulated AVG power and your 700w AVG/RMS power.

to quote yourself:
"If you don't know what those numbers mean, you really aren't saying anything important or significant at all."
 
AL (Sparky) does decent tune-up work generally included in a competative purchase price. Unlike some internet shops that would have you believing they offer several levels of peak & tune worth upwards of $40 above what the radio sells for. Anytime I have spoken to him on the phone, his answers have always been direct and honest with me. That said the Cobra 25 RFX package commands a price beyond it's value. As stated previously, aside from the increase in power, it will still be limited to the Cobra 25 features with a higher than normal current draw contained within a small unvented space, a receipt for disaster.
 
I think i'm going to have to just go with a 25 with out the add on amp. Someone else pointed out something i had been worried about and that is over heating,so i think I'm going to go with a 25 with mosfet final upgrade and leave it at that. Like i said the only reason i was thinking of the add on amp + the cobra 25 was because there does not seem to be any other place to mount a full size radio such as a 95T

Also thought about maybe the Magnum 257 but i cant find any info on the net about the over all size of the compared compared to a 25. Do any of you know if they are close in size?
 
257 would be a great choice....

25 dimensions
6-1/4 x 2-1/8 x 8-5/8


257 dimensions
Length: 9 1/2 " approx.
Width: 6 "
Height: 2 "


pretty damn close, and a helluva lot more radio....
 
"PEP" is the only true measurement of an amplitude modulated signal" bob85"

But only if you are measuring peak envelope power. Other wise, the other means of measuring power have just as much validity. If you like 'big numbers', using Pep is sure the way to do it. If you don't know what those numbers mean, you really aren't saying anything important or significant at all. What's the difference between about 700 watts Avg/RMS, and 1000 watts Pep? Absolutely nothing.
- 'Doc

(Ask him, he'll say the same thing if he's honest about it.)
1000 watts PEP is roughly 700 watts average if you calculate 1 and 1/2 times the resting carrier then you'll have the same figures which would show approximate modulation.
 

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