Category Archives: Uncategorized

WordPress is having a hiccup

There is a currently a problem with the links. I hope to have it fixed soon. Looks like it’s up and running now. If you experience any issues please contact me.

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Send in the clones

Isn’t it rich? Virtually every week I hear someone say, “I am building a clone of a Fairchild 670, or Pultec EQP1, or [insert name of famous piece of gear here]. Clone is just a euphemism for copy. That doesn’t … Continue reading

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Troubleshooting 101

About 40 years ago, I sold my National NC-33 receiver to my friend G. He used the radio for a while and then sold it to a person, who should remain nameless. When I asked G. how his customer was … Continue reading

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If a tube falls in the forest, does it make a sound?

I love reading the gushing descriptions about how tubes are supposed to sound. “Blow Hard brand 12AX7’s have chocolatey mid-range, solid bass and extended highs…” Really? I have more tubes than most people will have in 100 lifetimes and I … Continue reading

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7F7 loctal vs. 6SL7GT

I recently received an email from someone who built adapters to use 7F7 loctal tubes in place of 6SL7GT’s. He said that he didn’t like the sound of the 7F7 because the gain was too low. This was news to … Continue reading

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Death of value awareness is the death of fairness

Anyone who has ever been out to Leeds knows I love bicycles. An acquaintance has been searching for a new bike and has been asking me for advice. On several occasions he has found something within his price range. But … Continue reading

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On Free Advice

Some years ago I received a phone call: “Hello. My friend says you’re an expert on setting up moving coil phono cartridges. I have a problem: when playing piano records, during crescendos there is distortion on one channel only.” This … Continue reading

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Metal Vacuum Tubes

I will never forget the first time I saw metal tubes; it was a pair of 6L6’s in a Bogen amplifier from the early 1950’s. Metal tubes were introduced by RCA in a Technical Bulletin in 1935. The first metals … Continue reading

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Form, Function & Bling

Someone ordered an Amphenol 86CP12 plug and backshell a week ago. Amphenol made a whole series of these to mate with tube & connector sockets. They were available as 4 pin, 5 pin, 6 pin, 7 pin, octal, 9 pin, … Continue reading

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Eimac 4PR1000B pulse rated 1000 watt tetrode

This tube is more than 9″ (23 cm) tall. Maximum plate dissipation is 1000 watts. Max plate voltage rating is 30,000 volts. The 4PR1000B is pulse rated version of its cousin the 4-1000A. Filament takes about 21 amperes at 7.5 … Continue reading

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