Airline model 9004 schematic

[HighAndDry]

I accquired an Airline model 9004 amplifier.  It has one 15" speaker.  I can not seem to locate a schematic for it online.  One interesting note.  There is a tube diagram inside the cabinet.  It shows 6l6 tubes. The amp actually has 6v6 in it.  And one of those makes noise when tapped.  The amp also has a loud hum.   
   Any info would be greatly appreciated.

[sluckey]

I read somewhere that it's the same electronically as a Silvertone 1482. Compare this schematic and tube lineup to your amp and see if this will work...

http://el34world.com/charts/Schematics/files/silvertone/silvertone1482.pdf

[HighAndDry]

It is similar.  The tube  chart inside the cabinet lists 6L6GB for output tubes.  the actual amp has 6v6.  there are actually 6 inputs.  none of them are labeled microphone. 3 per  channel. Each channel having vol/tone controls.  And a vibrato footswitch input.
The tubes and chassis are located on the bottomof the cabinet while the controls are on top. the controls are connected to the chassis by a cable.  there is one 12AX7 on top with the controls

[PRR]

Welcome.

> cabinet lists 6L6GB for output tubes.  the actual amp has 6v6.

Some past owner blew a 6L6, didn't have another, stuck a 6V6 in the hole. Twice is not a shock.

If the cabinet clearly shows 6L6, you should use that type. 6L6 is "about twice the tube" of a 6V6. A 6V6 doing a 6L6's work may not live long.

The schematic may not be so different. You wire 6V6 and 6L6 about the same, but different PT and OT and maybe bias resistor. 2, 4, 6 inputs may be the same basic idea, repeated. The 1482 "Microphone" channel is the same as the Instruments channel except the two input jacks and resistors. As PA systems got better, "Mic" inputs fell out of fashion. All of these changes would be done at factory (or store buyer) whim, may have never been written down.

Is the amp barn-fresh, un-touched since 1973? Then it needs new power caps and likely a couple new tubes. Then some of the other small parts. If I know the work, these are hasty-wired amps and not pleasant to work in.

[HighAndDry]

one source tells me that it is the same amp as a danelectro centurion  http://www.danguitars.com/uploads/sm_275.pdf

[HighAndDry]

and also this   http://www.danguitars.com/uploads/dano_century30_1961.pdf

[PRR]

These are 6V6 amps. Your cabinet shows 6L6?

Still, it's gotta be something like one or another of these.

I'd still start with main filter caps (rectifier, cap, resistor, cap...) and tubes.

[DummyLoad]

and also this   http://www.danguitars.com/uploads/dano_century30_1961.pdf

270K Rk for 6V6? i think not...unless that's the undocumented power saver feature.    who says they didn't think green in the 60's.


--pete

[kagliostro]

Excuse me for the OT

Just to try to follow the signal path of the reverb, the input of the tank is on the Top or at the Bottom ??

http://www.danguitars.com/uploads/sm_275.pdf



Thanks

Franco

[PRR]

Top.

[kagliostro]

Thanks PRR

Now I think I can follow the signal path correctly

I'm not able to understand only the 1.5M resistor that connects the .01cap (on the plate of the 6CG7 tube)

with the .0022 cap on the Treble Control

Franco

[PRR]

Channel 2 is pretty simple.

Channel 1 adds a 6CG7 gain-stage. It drives the (piezo) reverb, but also the Ch 1 tone network. Because the 6CG7 has gain of about 16, a 1.5Meg+100K divider makes the gain similar to the Ch 2 gain.

[kagliostro]

The 100K you refer is the pot or the resistor on the right (near the 1M vol) or both  ?

Thanks

Franco

[PRR]

Reverb pot. Makes a direct 16:1 divider with the 1.5Meg.