Identify Flea Market Amp

[chunkitup]

First off please help me remember the resistors in the pic. I am restocking the bins and I want to buy these resistors but I forget what kind they are.

Second I am attaching several pics of an amp I picked up at a flea market. It obviously is made for hifi application and I only say that because of the screw terminals on the back. The bottles don't have markings so I don't know the types. If anyone could help me out identifying the amp and tell me is it worth the effort to get it in working order. Thanks

[Enzo]

I don't think hifi, no tone controls and very simple. I'd suspect more likely an intercom amp or low power PA amp, like for a school or office.

Worth the effort is up to you. I am sure you could work it into a little guitar amp.

[Pedro Vecino]

If the small transformer is a choke (it is connected between the positives of the electrolytic), where is the output transformer?

[Malcolm Irving]

... where is the output transformer?

It may have expected the OT to be mounted on or with the speaker(s).

[Pedro Vecino]

No doubt it will be, but these connectors are more dangerous than a monkey with two pistols

[Enzo]

Now that I look there, it does appear that the fourth terminal is wired to a filter cap, the third to pin 3 of the corner tube socket, and first and second to the 6v winding?

[chunkitup]

I dont know what to do with it. I would love to build a small hifi amp with set controls for tone (bass, treble). I have a pair of BR-1's speakers I built from parts express just sitting in my closet. Thing is I would need an output tranny, correct? As Malcolm said it probably had the output tranny on the speaker. Actually I would just like to get it working as it was supposed to and find a speaker with the tranny on it.

[mozz]

Could be a antenna amplifier? Or UHF convertor?

[Enzo]

I see no tuned circuits.

[rjb]

I have nothing to contribute regarding the amp.
Just wanted to give a thumbs-up for the Maple Donuts bag.

[chunkitup]

I have nothing to contribute regarding the amp.
Just wanted to give a thumbs-up for the Maple Donuts bag.

Yea buddy!!!!

[mikepukmel]

Wow, it is a choke indeed. That means, by the process of deduction, even with my limited electronics faculties, those screw terminals on the back of the amp are not quite OSHA/NIOSH safe for school children.



There's a video by a guy Mr Carlson's Lab, on Youtube where he repairs a really old tube amp built to install inside a church bell tower made around wartime. Maybe this is something like that.

[J M Fahey]

Where-do-those-screw-board-terminals hook-to???????
IF to the small "transformer" visible on chassis, then it IS an Output transformer; it should also have some terminals going to +V and last tube plate (it looks like a single ended job); now if it is indeed a choke (just 2 termimals) then the amp might use an external OT mounted on a speaker frame, most unusual because it sits at 300 to 400V DC above ground, on externally accesssible terminals, I very much doubt somebody would be so crazy as to do that, but hey, at least in theory anything is possible.

Please check and confirm here where doesn the "chocke/transformer" hook to.

[mikepukmel]

Where-do-those-screw-board-terminals hook-to???????
IF to the small "transformer" visible on chassis, then it IS an Output transformer; it should also have some terminals going to +V and last tube plate (it looks like a single ended job); now if it is indeed a choke (just 2 termimals) then the amp might use an external OT mounted on a speaker frame, most unusual because it sits at 300 to 400V DC above ground, on externally accesssible terminals, I very much doubt somebody would be so crazy as to do that, but hey, at least in theory anything is possible.

Please check and confirm here where doesn the "chocke/transformer" hook to.

J M Check out the image of the underside of the amp. It has a hole with a grommet that has 2 wires coming out about where the unidentified thing is on top of the chassis.

[mikepukmel]

I dont know what to do with it. I would love to build a small hifi amp with set controls for tone (bass, treble). I have a pair of BR-1's speakers I built from parts express just sitting in my closet. Thing is I would need an output tranny, correct? As Malcolm said it probably had the output tranny on the speaker. Actually I would just like to get it working as it was supposed to and find a speaker with the tranny on it.

oH YEAHHH Don't let this little amp die, after all its been through. It deserves another life!

maybe "Actually I would just like to get it working as it was supposed to and find a speaker with the tranny on it." and put the whole thing in a thick plexiglass case, so fingers and cats and dogs cant get at those screw terminals!