mandag den 29. oktober 2012

Kenwood TS-850 ALC problem - again

Ten months ago, I fixed the well-known Kenwood TS-850 ALC problem by lowering the resistor values on the DC-DC daughterboard (X59-1100-00) from 22 kohm to 18 kohm. The old horse ran again, and I was happy.

Now exactly the same problem has returned! By visiting Yamada Radio Clinic's archive and reading his article ALC Problem with TS-850 => DC-DC mod I learned that the transistors in the oscillator can degrade over time due to overload. This is probably what happened to my old TS-850 transceiver, which was produced circa 1990.

The new DC-DC board for Kenwood TS-850.

I decided to replace the old oscillator board with a new board using modern components. I followed the idea from Yamada Radio Clinic and made a replacement PCB containing the voltage converter ICL7660 and three more components. The result was satisfying and my Kenwood TS-850 now runs "just like new"!

If you want all details, you can visit my homepage where I've described the task and added more photos and a circuit diagram.

Lars Petersen 

2 kommentarer:

  1. rent a car is the most well known Islamabad rent a car organization for explorers approaching the capital of Pakistan. Have finish significant serenity with completely safeguarded rented car from Bahria car rental to move in the roads of Islamabad and close-by regions. Car rental services in Islamabad You can without much of a stretch book the administrations of the organization online even before setting a foot in Islamabad. Don't hesitate to converse with our delegate for promote enquiries.

  2. No matter which part of Pakistan you intend to travel to, AR Raheem Motors Rent a Car Islamabad provides you with a car of your choice to drive through the roads and highways of cities like Islamabad, Lahore, Karachi, Peshawar, and many others without having to force your way through the crowds at bus stations or railway stations. Spend time at a place for as long as you desire as you have your own vehicle to just get inside and zoom on the road to reach your next destination.We make it very easy indeed for our customers to book a car of their choice from us and get on their way to their destination as quickly as possible. With AR Raheem Motors Rent a Car Islamabad, you can book a car of your choice online . We have many options of car bookings for our customers and you can choose one to suit your requirements.