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Yaesu FT-101E/FT-102/FT-901/FT-902 High Voltage Filter Capacitors

The HV power supply capacitors are under particular stress due to the approximately 900 volts applied to them. If these capacitors fail, there is a good chance of loosing the HV rectifiers in the process and the possibility of a power transformer going with them.

For those restoring radios, given the original capacitors are now between 25 and 35 years old, changing them now will likely keep these radio's going for a long time to come.

The replacement capacitors are brand new made by Panasonic, rated at 85 deg. C and are 150uf at 500volts. These capacitors are 35mm in diameter, so fit the original mounting clamps perfectly.

These capacitors are 50% higher in capacity than the originals, which will "stiffen" the HV power supply and consequently provide sligthly higher peak output power due to the reduced sag in high voltage on voice peaks.

 

Kenwood TS-530S Cap Kit

The kit is comprised of the following capacitors (4 in all):

Qty 2  150uf/500v capacitors, 35mm diameter

Qty 2  470K ohm 1/2 watt resistors


 

Price | USD $28.95

 

 

Yaesu FT-101ZD High Voltage Filter Capacitors

The replacement capacitors are brand new made by Panasonic, rated at 85 deg. C and are 220uf at 500volts. These capacitors are 35mm in diameter, so fit the original mounting clamps perfectly. You can see from the pictures that the replacement capacitors are less than half the height of the originals. The photos show the old capacitors and the new ones installed in a Yaesu FT-101ZD.

These capacitors are 10% higher in capacity than the originals, which will "stiffen" the HV power supply and consequently provide sligthly higher peak output power due to the reduced sag in high voltage on voice peaks. I have also included in this kit two 470k ohm 1/2watt resistors which should be mounted across the two capacitors. Although not used in the original ZD design, the resistors serve two purposes; one is equalize the voltage distribution across the capacitors, and the other is bleed off the HV supply when the radio is turned off. With the current design, it is possible with low leakage capacitors (and if the tube filaments have not been powered up) for a substantial charge to remain for a long period of time after the off switch has been activated!

 

Kenwood TS-530S Cap Kit

The kit is comprised of the following capacitors (4 in all):

Qty 2  220uf/500v capacitors, 35mm diameter

Qty 2  470K ohm 1/2 watt resistors


 

Price | USD $30.95

 

 

 

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