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Valve testing

Most of the valve testing that I do is as a routine part of the service and repair of valve amps. There is NO CHARGE for the testing of valves as a part of a repair and valve testing is included in every valve amp service. However I’m approached from time to time by people who just want valves testing either to sell or for peace of mind. Valve testing is charged per valve, the price depends on the service you require. There’s a minimum charge of £16 for valve testing when not performed as part of a service. There are 3 valve testing services currently available. Test certificates are available as part of all of the services. For large quantity valve testing requirements I’m happy to negotiate a reduced rate. 

If you’re bringing me a repair and you have a couple of old valves you’d like me to test then no worries, that’s FOC and I can use them for the repair if they’re still good. If you’ve got a whole box, I may charge though!

Advanced Valve testing (£8/valve)

This new service uses a Ronald Dekker uTracer 3+ curve tracer. This is a digitally controlled curve tracer. This unit gives the following advantages:

Basic Digital Valve testing (£4/valve)

Basic digital valve testing is performed with an Orange VT1000 valve tester. There are more advanced valve testers around, and I’ve used traditional units by Avo in the past but this does exactly what I need at Ampworks. It tells me if the valve works and whether it’s suitable for the customer’s amp. This is a digitally controlled basic valve tester that gives a pass/worn/fail result as well as a matching value to allow the grouping of power valves into matched pairs or matched quads (or matched duodecads like this mesa boogie bass 400+ repair!). If you’re testing a dual triode then it gives a matching value for each triode, allowing you to determine if a valve is suitable for phase inverter duties. It’s not possible to test some valves on the VT1000, these must be tested on the advanced service.

The VT1000 performs the following tests:

VT1000 Valve tests:

Valve/tube types

I can test the following valve/tubes (Datasheets available from http://www.r-type.org/):

Octal power tube testing (pentodes and tetrodes):

Noval power tube testing (pentodes):

Noval preamp valve testing (dual triode):

Noval preamp valve testing (pentode)

Valve rectifier testing (Advanced service only)

Other ‘basic’ testing (£8)

If your valve type isn’t listed then I can probably still test it, a basic digital or advanced digital test can be performed on nearly all the valves that are commonly available on valve amps from the late 1950s onwards. However, these tests are only suitable for noval (B9A) and octal valve types.  For other valve types such as 7 pin, loctal, Duodecar, Rimlock etc, I also do a ‘basic’ test that checks basic function but cannot guarantee valve performance.

I’ve done these basic tests on:

MKT4/7 ( 7 pin Beam Tetrode) Sensibly equivalent to:- 7A2 – AC/Pen – APP4A – CV1683 – MP/Pen – KT42 – Pen4VA – A70B – N40 – P4VA
B65 (Octal Dual Triode) Sensibly equivalent to:- 13D2 – 6SN7GT – CV1988 – ECC32
B36 (Dual Triode) Sensibly equivalent to:- 12SN7GT – CV925
DL63 (Dual Triode) Sensibly equivalent to:- CV2912 – DH147 – 6R7G – OM4
U18/20 (Rectifier) Sensibly equivalent to:- 45IU – AU1 – CV1264 – FW4-500 – NU12 – FW4-800 – CV31 – 4/100BU – RV200/600
U50 (Rectifier) Sensibly equivalent to:- 5Y3G – CV1268 – CV3754 – 5Y3G/GT
L63 (Triode) Sensibly equivalent to:- 6C5 – 6J5G – CV1067 – CV1932 – VR67 – VT154
H63 (Triode) Sensibly equivalent to:- 6F5G – CV1073 – VT73

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