Rockford punch 201S

[Perry Babin]

It would be a shame to put those speakers in an environment that they may not survive. They are (were) highly desired. You may be able to sell them and buy a pair of subs. They even have their own wikipedia page.
Pioneer HPM-100 - Wikipedia, the free encyclopedia

 

[chipper]

Wow! I had no idea I got these from my grand parents a few years back since they remodeled there house. I got bored and wanted to mess around and switched the amps to all pass and they sound so loud and clean the bass is perfect! But yes it gets hot in the van and I don't want to mess these up.

 

[chipper]

It would be a shame to put those speakers in an environment that they may not survive. They are (were) highly desired. You may be able to sell them and buy a pair of subs. They even have their own wikipedia page.
Pioneer HPM-100 - Wikipedia, the free encyclopedia

I have my 201S now. I made a mistake the power supply is not blown has the original pwr supply devices (irf3205). Any one channel was shorted and had DC going through the left terminal. I replaced the irf540 & 9540 with another set of fets and it plays but with static. I checked MPSA06 & MPSA56 for that channel, those transistors seemed to be good. Next, is what i noticed when i was measuring the resistance for R150 & R152 (R152 had a measuring of 799 while the other was reading 11) Also R23 gets very, very hot near the transformer. Is that normal?

 

[Perry Babin]

R150 is open and will have to be replaced before you can do any more troubleshooting.

R23 gets hot. Unless it's so hot that it's desoldering itself, I wouldn't be concerned.

 

[chipper]

R150 is open and will have to be replaced before you can do any more troubleshooting.

R23 gets hot. Unless it's so hot that it's desoldering itself, I wouldn't be concerned.

Is R150 suppose to be around 10 ohms? I checked the remainder resistors from the good channel and those read 10 ohms. It's just R152 that is connected to Q115 that has a reading in the 700's. lmk what to do next.

 

[Perry Babin]

Yes. The two gate resistors are 10 ohms.

 

[chipper]

Yes. The two gate resistors are 10 ohms.

Okay I replaced the resistor I suspected to be bad and when I applied power to listen it still has distorted output I checked the source resistors those are good too, I don't know what's making it sound like that

 

[Perry Babin]

Do you have a scope?

 

[chipper]

No sir, no scope

 

[Perry Babin]

Lift D102 and D104 (one at a time, checking before lifting the second one) and see if either eliminates the distortion. It's VERY important to know which one eliminates the distortion.

 

[chipper]

Wow! I lifted D104 distortion gone! What's next? Or is that a bad smd diode?

 

[Perry Babin]

The diode is likely OK.

Confirm that R163 is within tolerance.

Check transistors Q116, 117 and 118.

 

[chipper]

Is it possible for only Q116 to fail? I measured the resistanc from all the connections and my meter kept making the beep noise indicating it has a short. I could not locate R163 but i found R164 and it's resistance is 1501 ohms. What's next?

 

[Perry Babin]

Yes. That's why I asked you to check it.

R163 is the 0.1 ohm source resistor.

 

[chipper]

Okay, Q116 is shorted from all legs and the Q117 & Q118 test fine.

Oh my bad, that resistor checks at 0.001.

 

[Perry Babin]

You'll need to replace Q116 and reinstall the two diodes.

 

[chipper]

Do you know whats the transistors polarity? Npn or pnp? Or the the part #?

 

[Perry Babin]

Q116 is an MMBT3906. You can replace it with the same. I generally replace them with MMBTA56s. If you're going to continue to work on Rockford amps, I'd suggest that you order at least 10 each of the following.

MMBTA06 Fairchild Semiconductor Bipolar Small Signal

MMBTA56 Fairchild Semiconductor Bipolar Small Signal

MMBT3904 Fairchild Semiconductor Bipolar Small Signal

MMBT3906 Fairchild Semiconductor Bipolar Small Signal