rascalseven
Well-known member
A buddy of mine got a Gates "Speech Input Console" given to him, and I'm checking it out to see about racking the 5 mic amps, or just using the transformers (BIG transformers) for making tube preamps of a completely different design.
I know nothing about the tubes this thing uses: Each mic amp uses one each of a 6J5 (RCA, black metal tube) and a 6F5 (Tung-Sol, black metal tube) both mounted in octal sockets. The 6F5 looks like a spark plug-- it has a conection on the top that snaps on and is covered with a cap held on by friction.
Each channel also has a large input transformer and an identically sized/shaped output transformer that feeds the routing switches going to the various bussbars. These transformers are not marked with manufacturers and models, but they look like the HA-1xx series UTC's (and, in fact, the output transformer has the H-1 type round pins with identical markings... so I'm guessing they might be UTC's???). The input transformer has 10 pins in 2 rows of 3 and another row of 4.
Sorry to be so detailed, but I'm just wondering if anyone out there is familiar with this series/era of Gates console. I cannot find a model number or serial number, just "Speech Input Console" on the front panel, and he has no documentation whatsoever.
Can anyone shed light on this board or, more importantly, on the basic design of the preamps? Are there any resources that might discuss mic preamp designs using tubes of this type?
Anything will help.
Thanks so much, guys, and peace!
JC
Oh, yeah, there's also a rectangular plastic device that I'm guessing is a capacitor of some type as it was mounted in parallel with a 33.9k resistor. It is flat-ish, about 1.25" long by 5/8" wide, and says "Micamold, Brooklyn, NY, USA, Type 340" on it. It also has an arrow indicating polarity (??) as these are mounted with the arrow facing the same way on all five channels. Any ideas?? Thanks again!
I know nothing about the tubes this thing uses: Each mic amp uses one each of a 6J5 (RCA, black metal tube) and a 6F5 (Tung-Sol, black metal tube) both mounted in octal sockets. The 6F5 looks like a spark plug-- it has a conection on the top that snaps on and is covered with a cap held on by friction.
Each channel also has a large input transformer and an identically sized/shaped output transformer that feeds the routing switches going to the various bussbars. These transformers are not marked with manufacturers and models, but they look like the HA-1xx series UTC's (and, in fact, the output transformer has the H-1 type round pins with identical markings... so I'm guessing they might be UTC's???). The input transformer has 10 pins in 2 rows of 3 and another row of 4.
Sorry to be so detailed, but I'm just wondering if anyone out there is familiar with this series/era of Gates console. I cannot find a model number or serial number, just "Speech Input Console" on the front panel, and he has no documentation whatsoever.
Can anyone shed light on this board or, more importantly, on the basic design of the preamps? Are there any resources that might discuss mic preamp designs using tubes of this type?
Anything will help.
Thanks so much, guys, and peace!
JC
Oh, yeah, there's also a rectangular plastic device that I'm guessing is a capacitor of some type as it was mounted in parallel with a 33.9k resistor. It is flat-ish, about 1.25" long by 5/8" wide, and says "Micamold, Brooklyn, NY, USA, Type 340" on it. It also has an arrow indicating polarity (??) as these are mounted with the arrow facing the same way on all five channels. Any ideas?? Thanks again!