Description
Platinum matched Quad AEG EL34 tubes produced by RFT (Rundfunk- und Fernmelde-Technik) in Mühlhausen, East Germany.
Detailed description
This EL34-verson is sold and labeled by AEG but is in fact a quality selection from RFT in Mühlhausen, East Germany. The RFT tube is easily identified by the dimple on top of the tube (see pictures). The tube has as single halo getter and stapled plates.
Because of the high quality of this tube several major manufactures like AEG, Siemens, Valvo, Philips and Telefunken have sold this tube under their own brand label. And this is exactly the case for this quad. It is known that AEG has set special quality criteria for their third party tubes. So it may be assumed that these tubes belong to the best EL34 that RFT has produced.
The RFT EL34 is known for its excellent sonical reproduction, sturdiness and longevity; especially in comparison to the Chinese and Russian new production EL34. Sonically many prefer this tube above the later productions. I refer to the many reviews on the web
The quad has excellent test values and new looks. Extremely well matched !
Note: my tubes are often not the cheapest. But is very hard to find better tubes !
Test method
Mutual transconductance, plate current, gas and shorts tested with: AVO CT-160 (Dutch army tester), Utracer3+, AVO Valve Data Manual 23rd edition 1981, Philips 1532, RFT stabilised power supply and 2x Keithley 2700. Test conditions: Anode 250V, Screen 250V, Grid -13.5V, Filament 6,3V, Rated Ia = 75mA and rated transconductance 11mA/V. Please read our test page.
Test results
The measurement data below show that the tubes are platinum matched.
| Valve
V306 |
Ia (plate current):
Transconductance (Gm): Gas test, Shorts test: |
110 mA
11,1 mA/V OK |
> NOS
> NOS
|
| Valve
V307 |
Ia (plate current):
Transconductance (Gm): Gas test, Shorts test: |
102 mA
11,0 mA/V OK |
> NOS
> NOS
|
| Valve
V308 |
Ia (plate current):
Transconductance (Gm): Gas test, Shorts test: |
107 mA
11,3 mA/V OK |
> NOS
> NOS
|
| Valve
V309
|
Ia (plate current):
Transconductance (Gm): Gas test, Shorts test: |
109 mA
11,3 mA/V OK |
> NOS
> NOS
|
Telefunken measuring values for new unused tubes:
- The rated emission value for a new EL34 is: 100 mA.
- The rated transconductance value for a new EL34 is: 11 mA/V .
For Telefunken specs info see last picture
Test condition & equipment:
Mutual transconductance, plate current, gas and shorts test equipment: AVO Mk IV (Dutch army tester), RFT stabilised mains, Utracer3+, Philips PE 4832, 2x Korad KA3005P programmable power supply, 2x Keithley 2700 and 2x Fluke 145. Test conditions: Ua (plate voltage) = 250 Volts, Us (screen voltage) = 265 Volts, Ug = -13,5 Volts and Uf = 6,3 V ± 3% (factory conditions). Please read our test page.
Summarized description
| Tube type | EL34 |
| Quantity of Tubes | One quad |
| Brand | AEG |
| Manufactured by | RFT Mühlhausen, Eastern Germany |
| Date code | None |
| Plate Construction | Stapled grey plate |
| Getter Construction | Halo getter |
| Print Condition | Nice; see pictures |
| Box included | Factory box |
| Equivalent tubes: | 6CA7 |
| General test results | NOS |
Please read our test and shipping policy before buying !
