All tubes are tested on a Hickok 539C, Maxi-Matcher, and a George Kaye Small Signal Tube Checker, and guaranteed to function within specified limits for 30 days (rectifiers for 6 months). Do not operate power tubes without having you amplifier's bias checked/adjusted. If you have questions about biasing,  take the amp to a qualified technician. 

Defective tubes must be returned within 30 days or purchase. 
All good tubes returned for credit (within 30 days, no exceptions) will be subject to a 25% restocking fee
($15 minimum) and MUST be returned in the same condition as received (including the condition of the
markings on the tubes and the boxes with NO scratches on tube bases). Tubes not returned in
original condition will not be accepted. Contact us before returning items. Include a note with the
problem description and whether you'd like a credit or exchange. Include a copy of your original invoice.

All power tubes must be operated under the proper conditions or all warrantees are void. Most amplifiers
require re-biasing for new power tubes. Biasing must be done by a qualified tube amp technician. 

Power tubes are matched for both mutual conductance (within 5%) and current draw (within 3mA but
usually closer @ Vplate ~= 400Volts) on a Hickok 539C and a Maxi-Matcher. Closer matching available on request. 

Prices and availability subject to change. Please call or email Ron@unclespot.com to check availability and
current pricing.

Click HERE to return to the Uncle Spot main page