These are the last of the ECC88 made in Heerlen, Netherlands. This listing includes Orange Globe labels and A-frame getter supports as well as earlier double-stage getter support. All have the Heerlen triangle etched in the glass. SoundByDoc has classified five main types of Heerlen ECC88: T1 (1957): Ultra rare pinched waist, D getter. T2 (1958-1959): D getter GA0 GA1 GA2 code. T3 (1959-1962): Large halo getter GA3, GA4, GA6, and some GA7. T4 (1962-1968): Small halo getter GA7, GAA, GAB, GAC. T4bb: same as T4 but with at least some of the bugle boy logo visible. T5 (1965-1972): Orange Ink, Dimple Getter, or A-frame getter support (any or all of these qualities makes it a T5).
Your tube has been fully tested on a computer-regulated, USA-made Amplitrex AT1000 on Fixed Bias setting with like new, NOS results (tNOS). Here's what that means: to qualify for this listing, several stringent conditions must be met: The transconductance for each section must measure between 10000 uMhos and 15000 uMhos, consistent with original 1965 RCA, Western Electric, Sylvania, GE, and/or Tung-Sol datasheet specifications for new tubes of this type. The tube must also show no shorts, show a gas current less than 1.5 mA, and a heater-to-cathode leakage of less than 10 microamps (10 uA). The tube might have mechanical wear or have the label rubbed off - these are very old! Used-testing tubes are available in a separate listing at a significant discount. Every tNOS or Used Good tube you receive from Sound By Doc is guaranteed against failure for 60 days after purchase, an industry extreme!
OPTIONS (use offer feature in Reverb):
Want a regular white box? $1 extra per tube
Want the test results recorded on your box, too? $3 extra per tube
| Listed | 5 months ago |
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| Condition | Very Good (Used) Very Good items may show a few slight marks or scratches but are fully functional and in overall great shape.Learn more |
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