AMI power junction boxes
AMI jukeboxes of the late 1950s through the Continental series employ
a junction box where the AC power comes in from the line and is distributed
to various parts of the machine. This box also has a DC power supply and
associated fuses. The service manual typically shows this as part of the
cabinet, with exploded views but no schematic. The exact configuration
varies between models, but the schematic below for a Continental 2 is
typical of the lot.
Note that in the original design the power transformer is unswitched, making
the DC circuits live regardless of the position of the power switch. This
was apparently to allow selections to be made even if the jukebox was powered
off.
When rebuilding these machines, I add a grounding cord, change the power
switch to double-pole, and move the transformer to the switched side of
the supply. As the cabinets are non-conductive, it will be necessary to
add grounding wires or straps to the exposed metal parts of the jukebox
to ensure safety. The modified junction box looks like this:
Parts list
The following is a listing of the continental 2 junction box components
along with available replacements.
| DESCRIPTION |
AMI Part No. |
Replacement Make |
Replacement Part No. |
Mouser Part No. |
Notes |
|
|
|
|
|
|
|
|
|
|
|
|
| Filter Capacitor |
F-10318 |
Sprague |
36DX242G050AA2A |
75-36DX242G050AA2A |
Note 1 |
| Power Switch |
F-235 |
NKK Switches |
S21A |
633-S21A |
Note 2 |
| Socket, 4-pin |
F-880 |
Cinch |
S-304-AB |
538-23043 |
|
| Fuseholder |
F-861 |
Bussmann |
BK/HKP |
504-HKP |
Qty. 3 |
| Fuse clip |
F-2219 |
Keystone |
3523 |
534-3523 |
|
| AC receptacle |
F-850 |
Kobiconn |
15AC021 |
15AC021 |
Qty. 6 |
| Terminal strip |
F-1298 |
Keystone |
4188 |
534-4188 |
|
| Power Cord |
F-5990 |
Volex |
17513-10-B1 |
686-17513 |
Note 3 |
| Strain relief |
S-2321-D |
EPD |
MP6N4 |
561-MP6N4 |
|
| Rectifier |
F-5113 |
Rectron |
MP-154 |
583-MP154 |
Note 4 |
| Capacitor clamp |
F-10319 |
EPD |
561-B1250 |
561-B1250 |
Note 5
|
| Fuse 2A fast |
S-720-A |
Bussmann |
BK/AGC-2 |
504-AGC2 |
|
| Fuse 8A fast |
S-2720-B |
Bussmann |
BK/AGC-8 |
504-AGC8 |
|
| Fuse 1A slow-blow |
S-721-E |
Bussmann |
BK/MDL-1 |
504-MDL1 |
Qty 2 |
| Solder lug |
|
Keystone |
7313 |
534-7313 |
Note 6 |
Notes
- Replacement part is 2400 microfarads vs. original 1000; screw terminals
as opposed to solder tabs. Alternate original part number F-5051.
- This is a double-pole switch to disconnect both sides of the line for
safety.
- Grounding cord with three-prong plug, 10 feet long.
- Bridge rectifier. Connect transformer leads to (~) terminals, output to
(+) terminal. (-) terminal is unused.
- Nylon clamp, original is metal. Alternate original part number F-2672.
- Three needed, two for capacitor and one to secure ground wire under
transformer mounting bolt.