Burns Orbit Amplifiers
A few of these turning up these days. They're some of the earliest mainstream transistor guitar amps, and Orbit Twos and Threes can still be had for a few hundred pounds. If you want to be pedantic, the Vibrato effect is actually Tremolo on all Burns equipment. All models except the Orbit Two have a Studio/Boost switch which cuts the drive level to the output transistors.
Just a personal opinion but, interesting as they are, these are some of the worst examples of mechanical design and assembly you're ever going to see. Think twice if someone says "I found this on eBay; can you just have a quick look at it for me." Expect multiple age and corrosion related faults, especially high resistance solder joints, and expensive, obsolete parts. As far as sound goes, the simple bass and treble controls on the Double 12 seem to be a much better arrangement than the preset selector tones on some of the other models .
The power output of the Orbit Three was quoted as sixty watts. If you look closely at the advert on the left, they mention that this is peak power (2 x rms). That gives a target of 30watts rms if you're trying to repair one.
Adverts for other Burns models quoted power output simply as 'British'. That description was generally applied to rms values at the time.
Things became clearer when Baldwin took over and started to quote 'British rating at less than 10% distortion'.
10% distortion through an early transistor amp probably isn't something most people would want to listen to.
STILL WORKING ON THIS PAGE. For Orbit Three schematics and layouts click HERE
Burns Orbit Two
880. Orbit Two
Available initially as a 2 x 10" and later as a 1 x 12"
16"h x 121/2"w x 91/2"d
Orbit Two 2 x 10"
Power output: 40 watts, British rating.
Mains supply: 200 to 250v. A.C., 40/60 c.p.s., operation without adjustment. Supplied complete with 15 ft. of three conductor mains lead.
Speaker: One 12 in. Orbital heavy duty speaker.
(Also available as a 2x10")
Channel One
-
Inputs: Two high impedance
-
Controls: Volume, Bass, Treble, Vibrato Intensity and Speed
Channel 2
-
Inputs: Two high impedance
-
Controls: Volume, Treble
OPERATION. In general, Channel One should be used for lead instruments like the solo guitar, or accordion, whilst Channel Two should be used for rhythm guitar, second accordion or microphone. The Orbit Two is not suitable for bass guitar.
Amplifier 75 gns
Catalogue details
Burns Orbit Three
plus
Orbit Three schematics (and new layouts) have moved to HERE
881 / 885. Orbit Three Standard
882 / 886. Orbit Three Reverb "with extra dimensional control" if you're into that sort of thing.
There are four versions of this unit:
'Orbit Three' 3 x 10"
-
881 (no reverb)
-
882 (reverb)
'Orbit Three Double 12' 2 x 12"
-
885 (no reverb)
-
886 (reverb)
Catalogue details:
Dimensions 21"h x 25"w x 10"d
Weight approx 37Ib
Output power 60watts ( peak)
Measured output power with a continuous sine wave is just over 30watts rms at clipping into 2ohms.
Worth noting that, although Burns advertising didn't seem too bothered, the 'Orbit Three Double 12' is not the same as an 'Orbit Double 12' (see next section).
882 Orbit Three 3 x 10" with reverb
Burns Orbit Double 12
Channel 1 gets a rotary Bass control instead of the tone selector switch.
Orbit Double 12 Reverb
An amp that Bert Weedon used and spoke very highly of. His own Double 12 (right) was part of a collection sold at auction by Bonhams, London in 2012.
There doesn't seem to be any advertising available for this one, but there's a demo on YouTube at:
Photograph courtesy of Bonhams auction house
You don't often get the chance to hear an Orbit on stage, so check out the 5.6.7.8s on YouTube in 2022.
https://youtu.be/4ncsA8I94EQ?si=eKb49JwqfUMtNdTs
(Google says the guitar's a Teisco EP-1L)
Difficult to tell from the front whether it's a Double 12 or an Orbit Three Double 12. They seem to have stuck the same logo on both amps.
Burns Orbit Six
883. Orbit Six Standard
884. Orbit Six Reverb
Speakers: 6 x 10" 3ohm Celestions or 3 x 12" 6ohm Fanes
Dimensions: 23"high x 331/4"wide x 12"deep
Advertised output power: 100watts (British)
Weight: (insert large number)
Orbit Six 3 x 12" with reverb
Baldwin Orbit 75
Catalogue number 610
Although there were still a lot of Burns versions around, this was the only Orbit in the Baldwin 1966 catalogue. It's a mix and match, transition model using the new Baldwin control panel styling and old Burns cabinet shape.
The speakers have moved around to what used to be the back and you can actually see the controls on stage (at last).
They can be found, now and again, with knobs from the Sonic range.
Catalogue Description
Power Output: 75watts (British Rating) at less than 10% distortion
Loudspeakers: Two extra-high flux, heavy duty, 12 inch, 6 ohms each
Mains Supply: 200-250 volts, 40-60 cps, no adjustment required and 100-125 volts, 40-60 cps, no adjustment required
Size : -
Weight: -
Channel 1:
-
Inputs: Two high impedance, 200k ohms
-
Controls: Volume, Bass, Treble, Vibrato Intensity and Speed, Reverb Dimension, Three-degree Treble Boost buttons, Studio-Power Boost button
Channel 2:
-
Input: Two high impedance 200k ohms
-
Controls: Volume, Bass, Treble
General:
-
Built-in reverberation, Vibrato and Reverb footswitches
-
Mains on-off switch and neon mains indicator
The 75 was available in the same range of colours as the Baldwin Sonics.
Saddle Tan
Jay Blue
Gold
Charcoal Grey
Silver Jet Black
Cardinal Red
Sage Green
Tangerine
Honey
White.
Also available was the Orbit Stand, catalogue number 889.
"Built from chrome plated steel tube. The top section incorporates dual friction clamps which enables the cradle to be lifted."
Semiconductor Details
1B40K20
Silicon Bridge rectifier
If: 4A
Vbr: 200V
NKT213
PNP Germanium
Vcb max: 32V
Vce max: 18V
Veb max: 10V
Ic: 250mA
Ptot: 200mW
Hfe: 50
NKT217
PNP Germanium
Vcb max: 60V
Vce max: 40V
Veb max: 10V
Ic: 500mA
Ptot: 200mW
Hfe: 50
NKT304
Vcb max: 30V
Vce max: 20V
Veb max: 15V
Ic: 2500mA
Ptot: 750mW
Hfe: 50
PNP Germanium
NKT403
PNP Germanium
Vcb max: 80V
Vce max: 32V
Veb max: 40V
Ic: 10A
Ptot: 50W
Hfe: 50/150
NKT404
PNP Germanium
Vcb max: 60V
Vce max: 32V
Veb max: 20V
Ic: 10A
Ptot: 50W
Hfe: 50/150
NKT452
PNP Germanium
Vcb max: 36V
Vce max: 32V
Veb max: 10V
Ic: 3A
Ptot: 43W
Hfe: 30/90
OC25
PNP Germanium
Vcb max: 40V
Vce max: 40V
Veb max: 10V
Ic: 4A
Ptot: 23W
Hfe: 15
OC35
PNP Germanium
Vcb max: 60V
Vce max: 32V
Veb max: 20V
Ic: 8A
Ptot: 30W
Hfe: 25
OC706
PNP Silicon (The only silicon transistors in the circuits, used as channel input devices)
No other data available
