There were three different varieties of Charlie Christian pickup produced by Gibson, and all three are distinguished by the polepiece: 

1. The first of these was produced from 1936 until mid-1938 and had a plain blade polepiece. The coil was wound to about 2.4 kΩ resistance using AWG 38 enamelled wire.
2. The second type was introduced on ES-150s built from mid-1938 onward, and featured a polepiece that had a notch cut out below the second (B) string. This modification was made to lower the volume of the B string, which sounded significantly louder than the other strings. At this time the coil was wound with a finer wire (AWG 42) resulting in more turns and an approximately 5.2 kΩ resistance, which gave the pickup a higher output.
3. The third pickup was available on the Gibson ES-250, which was available beginning in 1939. The blade on this pickup had five notches, each located between the strings. This pickup also had a more compact internal design. It featured a cobalt steel slug that was small enough to sit directly under the pickup.

The sound this pickup produced is clear—thanks to the narrow string-sensing blade—and powerful because of the relatively high resistance of the coil. Uneven magnetic flux within the steel magnets could cause some distortion in the signal. Electromagnetic hum was a big problem with these pickups because of their large surface area and utter lack of shielding.

Gibson EH-150 Amplifier was also used by Django and having looked at the interior wiring shots its a marvel that our man was not electrocuted mid solo flight.

The EH-150 amp cabinet was covered in "Aeroplane cloth", luggage tweed, with contrasting vertical brown stripes. A black perforated aluminium grille protects the ten inch "Ultrasonic High Fidelity Reproducer" speaker. Later Gibson would often affix red stickers onto the back of speakers with the printed text "Ultrasonic Speaker". Especially during the '60s and '70s. Chassis were mounted at the bottom of cabinets.  The features of the early EH-150 amp include one input for microphone and three inputs for instruments, separate volume controls for the microphone and instruments sections, a bass-tone expander switch, and an "Echo" extension speaker jack.

For the microphone input stage of the early EH-150 one 6F5 tube (high mu triode) was used and one half of an 6N7 (dual high mu triode) to provide gain for the instruments input and the second half to a second gain stage for both input stages, one 6C5 tube (medium mu triode) to serve as a third gain stage and a transformer to split the phase of the amplified signal into two 6N6 output tubes (direct-coupled power triodes. One 5Z3 rectifier tube was also used.

Gibson 1936 EH-150 Demo

EH-150 Detail Shots

Amplifiers of the day were just as basic as the early electric guitars, if not more so. The EH-150 had in fact arrived before the ES-150 guitar, as partner to Gibson’s EH-150 lap-steel guitar (these were actually Gibson’s first genuine electric guitars, and the amplifier retained the lap steel’s “Electric Hawaiian” designation). The EH-150 originally carried a single 10" speaker (later a single 12") and was powered by a truly archaic circuit design, and now-obsolete preamp and power tubes, but it was an impressive beast for the mid ’30s. Even when the circuit had evolved a few years later to employ 6L6 output tubes, the amp still only produced around 15 watts at best, but that 15 watts sounded pretty darn loud next to any acoustic-only rhythm guitarist hacking away in the rhythm section, so these amps were enough to unleash the guitarist as soloist on the big-band stages of the day.

This hollowbody Archtop guitar with Period case and matching EH-185 Amplifier made its debut in 1939.

The following year the Gibson catalogue made the proclamation, “Gibson has created the best electric guitar possible to make.”

It became a favourite of bluesman T-Bone Walker, who turned to it extensively during the ’40s and ’50s.

Charlie Christian, Alvino Rey and Tony Mottola also fell for the instrument. Based on the ES-150 but with several bold upgrades, the ES-250 featured a larger body, refined fingerboard and snazzier accoutrements like deluxe headstock, tuners and tailpiece.

Perhaps its defining characteristic is its bar pickup with six mini blades that performed as separate polepieces for each string (now known as the “Charlie Christian pickup”).

This was a short-lived model.  Jazz guitar pioneer Charlie Christian owned two of the 70 that Gibson made. It featured the bar pickup that many jazz players still think is the best jazz pickup that Gibson ever made.

It was superseded by the ES-300, which featured Gibson’s first adjustable-pole pickup,  This was the Electric Guitar that Django used when touring with Duke Ellington but with a strange Hybrid Amplifier.

Gibson EH-185 Amplifier - Vintage Pre War Gibson Amp Demo

Christian used two of these amps one plain brown and one as illustrated.