Obituary(s) To A Filter Cap And A 6X4 Rectifier Tube

Sam Neal


I sadly report the passing of two QRP radio transmitter components.

( #1 ) Passing ( Suddenly! ) of a 22 mFd/450 Volts DC Filter capacitor.

Born approximately 2007 in China ( The People's Republic There-of )

Passed ( suddenly ) just before the 4 States QRP Group Net, 0130 Z - 7122 kHz
24 May, 2017 at 01:15:05Z

Born in People's Republic of China to operate continually at 450 VDC.
Passed suddenly and in a spectacular manor while operating at approximately
380 VDC

We also sadly report the associated passing of two 1 Ampere fuses and one 6X5


( #2 ) Suddenly, 01:15:06 Z one 6X5GT/G CHS/Jan rectifier tube.

6X5/GT/G/JAN/CHS served proudly during the World War 2 conflict assigned to
the United States Navy.
Two innocent 1 Ampere fuses lost their lives as a result of the above

Services will be This coming Wednesday by the P&H Garbage Pick-up Service
Pall-bearers will be Cooter and Bubba.

Internment will be shortly there-afterwards at The Liberty County Texas


This is the first failure I have had with these small sized fiter caps. I
suggest operating these imports will below heir rated Voltage limits. The
above components were in the built-in power supply of a clone-kit of an Ameco
AC-1, with a Ken-Rad 6V6 tube as a crystal oscillator.

The transmitter was not being used when the filter cap failed, just minding
it's own business, awaiting net time.

The current rush took the 6X5/G/GT with it, and it's rolling off the desk top
and playing Humpty Dumpty didn't help it any at all. So far, no problems with
the replacement 22 mFd. 450 VDC cap.

All kidding aside, have any of you had problems with these type capacitors,
operating well below their operating Voltage, failing? The value and Voltage
ratings are well marked, but no manufacturer's info is shown. I either bought
them in small lots off of E-Bay purchases, or the filter cap was supplied with
the kit - I forget.

Due to failure with 50+ year old paper filter caps in older boat anchor rigs,
I routinely replace the filter caps and also add a fuse before ever
transmitting the first dot with them. I had hoped that operating well below
it's Voltage rating would help, but it didn't.

Any comments on similar incidents would be appreciated.


Sam Neal N5AF

Celebrating 60 Years In Amateur Radio

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