Dating a fender amp bt serial number
If the diamond mark is missing, the tube was likely made by Siemens or another of the Dutch Philips companies.The codes printed on the glass may be Telefunken codes, but without the diamond mark in the bottom glass the tube was not actually made by Telefunken.
After the little problem with the USB rs232 Converter(now I go directly to RS232 on my Systemboard) it works really great. On the front the power and the anode voltage LEDs are located.
av 4-61 aw 5-61 ax 6-61 ay 7-67 az 8-67 ka 1-44 kb 1-50 kc 4-54 kd 12-46 ke 2-37 kf 9-40 kg 11-37 kh 2-50 ki 4-57 kk 10-41 kl 12-32?
km 10-42 kn 5-57 ko 11-32 kp 5-54 kq 6-57 kr 4-42 ks 7-63 kt 8-63 ku 10-32 kv 5-39 kw 6-54 kx 9-68?
Thank you from Germany Freddy Utsch 20th of July 2017, Andreas Neuffers u Tracer and especially the tube adapters are a remarkable piece of craftsmanship!
In the future I will build a little case, now I made quick and dirty noval and octal adapters to measure el84 pentode, ecc 83 85 88 double triode, and el34 6l6 6p3s.Telefunken was an old German company created back in 1903.