No Name 2 Pill 1446 Amp

[Tucker442]

I've got this 2 pill front says Galaxy amp with 1446 finals. It went from 150 watts to about 55. I opened it up found a burnt resistor next 2 one of the finals. I bought Chinese 1446's replaced the resistor and now have nothing. Could both the Chink finals be bad? I have a transistor tester and Fluke 88 not sure how to check them any help would be appreciated, I did install the end with the angle on it the same way the old ones came out. Thanks in advance for your time.

 

[tba02]

Did you replace/check the fuse?

 

[Crusher]

150w, was this dead key/ carrier? If so way too high. 40-50w DK max out of amp. The resistor that was burnt on base of one of the pills/ transistors is a sure sign it's probably bad. Not sure which Chinese pills you put in it. But if bias went bad, could have popped new pills as soon as you hooked up.

With fluke, you can use diode check mode. Red lead to base and black lead to emitter ( these are the opposing tabs that get soldered to ground). Should read around .5-.6v. Then leave the red lead on base (input side) and put black lead on collector ( this is output side). Should read around .5-.6v. The transistor has to be out of circuit or at least lift tabs so they are not connected to solder tabs.

 

[Tucker442]

150w, was this dead key/ carrier? If so way too high. 40-50w DK max out of amp. The resistor that was burnt on base of one of the pills/ transistors is a sure sign it's probably bad. Not sure which Chinese pills you put in it. But if bias went bad, could have popped new pills as soon as you hooked up.

With fluke, you can use diode check mode. Red lead to base and black lead to emitter ( these are the opposing tabs that get soldered to ground). Should read around .5-.6v. Then leave the red lead on base (input side) and put black lead on collector ( this is output side). Should read around .5-.6v. The transistor has to be out of circuit or at least lift tabs so they are not connected to solder tabs.

Thanks Crusher for the info to Tba02 it does light up and keys the relay when I key up the radio just output is Zero and with the amp off the wattage from the radio does go through the amp so it's not like a SO 259 issue or something like that

 

[Decoder]

The real way to check them is if you have transistor checker that does HFE. Even the chink ones can show a high gain and can still be fake. I bought a few of them chick ones and out of 25 of them 4 could be used. But I will tell you this the ones that did work has better gain and matched better then the original one, "who figured" I have all mine checked by a fellow here in NJ, see if you can find someone by you that has the knowledge to do this and it will save you a lot of time and money. "Just My Two Cents Worth"

 

[tba02]

I only mention it as I have had a similar amp show power but no output - changed the blade fuse (ATO) and was back in business.

 

[psycho]

Using cheapo generic Chinese replacement transistors is like playing Russian roulette with 6 live rounds in the cylinder.....you lose. RF Parts still stocks the SD1446 transistors.
I once bought 2 generic 1969 finals on Ebay and they didn't work, lesson learned.

 

[Tucker442]

Decoder who in NJ checked them for you I live in NJ also but there are no radio guys close to me. Ask the guy if he would check mine for me I would not want to bother anybody but I was ready to throw the amp away until I read a thread about chink finals being hit and miss

 

[Decoder]

I asked him and he said he can check them, No problem. I don't know where about in NJ you are. But I know he works over in Monroe by exit 8A, maybe you two can get together, I believe he is still in TR and hasn't moved yet.