Yellow Jackets Power Reduction / Yellow Jacket Cathode Bias Pentode Volume Reduction 5070 JJ EL84 Kit Pair

Yellow Jacket Cathode Bias Pentode Volume Reduction 5070 JJ EL84 Kit Pair Click on image(s) above to view larger

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Originally designed by Andy Marshall of THD fame yellow jackets current limiting voltage conditioning adaptors for use in most 20 to 100 watt amps that use 6L6, EL34, 6550 or 6V6 output tubes. They Allow you to reduce the output of your amp and change the characteristics by using EL84.
Volume Reduction by between 50% & 70%

Our Cathode Bias Pentode kit is designed to reduce the volume of your amp by between 50% & 70%. This Kit consists of 2 Yellow Jackets Cathode Bias operation valve converters and Two Matched JJ EL84 Output valves. Yellow Jacket has an Overall height with the EL84 fitted of approx. 5 inches. So please check your clearance before ordering

The Yellow Jacket Cathode Bias Pentode operation is for amps with a cathode bias circuit only.

These are also known as self bias as the cathode biased power valves have a bias resistor connected from their cathode to ground. The ground wire of the YJC is used to bypass the amp's cathode bias components so the Yellow Jacket converter's internal bias components are used instead. So you will need to check your amps circuit operation before purchase.

Examples of amplifier that use this circuit are Marshall Origin 20, Marshall DSL20, Carr Rambler, Carr Viceroy, Fender 57 Tweed Deluxe RI, Fender Champ 600,

These Pentode operational converters not only drop the volume of your amp but also changes the operational mode to class A . This provides a VOX style tone with an increased touch sensitive response. The Yellow Jacket cathode bias Pentode operation is for amps with cathode bias circuit. So these can be used on other cathode bias amps in your collection.

These specialized power reduction , current-limiting voltage conditioning adapters converts your amplifier from Class AB to Class A operation and drops output power by using EL84 without modification or rebiasing. These converters for Fixed Bias amps cleverly provide the necessary plate voltage drop and current limiting on the screens as well as blocking the amplifiers grid bias voltage while configuring the EL84 in a Class A.

We Offer one Kit 5070 Pentode Operation

Pentode Yellow Jacket will reduce your amps output by between 50% to 70%

A Marshall Origin 20 with 2 EL34 would provide 20W RMS power output.
In Pentode Operation with 2 Yellow Jackets approx. 7 to 12 Watts

Please note
Yellow Jackets cannot be used in amplifiers with plate voltages in excess of 515VDC and over 100 watts rms. It is not suitable for Peavey 6505, Bugera 6262 Infinium, Bugera 333XL Infinium, Orange OR120 and most valve bass amplifiers such as Ampeg SVT, Hiwatt 201, Marshall VBA etc

Product Measurements by Type
Item Diameter 1.301 in.
Item Height, without pins 2.18 in.
Item Height, with valve 5.0 in.

This Kit consists of

2 Yellow Jackets Cathode Bias Pentode operation valve converters
2 Selected JJ EL84 Output valves



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