Kenwood KR-5010 receiver

[TomTom4049]

Hello all. I know the whole STK0050 thing has been done absolutely to death and primarily in the Pioneer SX-780 forums. Be that as it may, I just bought a Kenwood KR-5010 on the cheap, mainly because my late brother had one and I always liked it.

It has SANYO STK0050 Darlington Power Packs in it I discovered looking at the schematic. It actually is to arrive tomorrow so I haven't put paws on it yet.

At any rate I was thinking that if it has bad DPP(s) and it seems nothing is available but knock-off fakes, is it possible to use a STK1050 instead? The main difference I see is the 1050 has internal emitter resistors and the 0050 doesn't. From the look for the way the emitter resistors are arranged you may not necessarily have to make use of them.

 

[Watthour]

I have a couple SX-780s running on "fake" modules. They seem to do reasonably well with efficient 8Ω speakers, only one pair at a time. The ultimate solution is the replacement module, so well documented in the Pioneer forum.

Don't wish for the worst, however. The original modules may be just fine. Hopefully, the problem is not within the TA-1001 IC.

 

[TomTom4049]

Thanks for the words of wisdom and encouragement. I've got fingers and toes crossed.

 

[TomTom4049]

Ok I have the unit in hand. One bad STK0050. I've ordered a couple of STK0060 replacements and have a question as to the emitter-collector resistors. In STK0050 form it has .22 ohm emitter resistors. (just to note, a Kenwood KR-4010 had .33 ohm emitter resistors for it's STK0040 darlingtons). From sample schematics on the STK0060 I see .47 ohm emitter resistors used. The .22 in this unit is obviously correct for the 0050. Suggestion on what I should swap them to for use with the 0060?

 

[Watthour]

I would keep the 0.22Ω resistance even though the STK0060s are rated for higher current. The rest of the amp topography is designed for the original resistance, and the resultant emitter bias.

 

[TomTom4049]

I'll take your advice and leave the.22 ohm resistors in place. Thank you for your input!

 

[TomTom4049]

The STK0060 Power Packs are too long top to bottom to fit the Kenwood's chassis so thats a bust. I decided to go with DIY replacements for the power amps.