This page shows numerous photos of my first Hell Feldfernschreiber (Feld-Hell) machine. All photos have been down-sampled. They are available as full-resolution jpg files. You can contact me via the menu at the bottom of this page.
- [Equipment set]
- [Amplifier box]
- [Keyboard and character drum]
- [Base module]
- [Printer module]
- [Tips for taking good photos]
©2004-2017 F. Dörenberg, unless stated otherwise. All rights reserved worldwide. No part of this publication may be used without permission from the author.
Latest page update: 31 January 2017
THE FELD-HELL SET IN ITS "TORNISTER" CARRYING CASE
Fig. 1: front-view of the Hell Feldfernschreiber
(compartment with paper tape rolls closed (left) and drawers slightly pulled out(right))
Fig. 2: electronics box partially pulled out of the case
Fig. 3: printer/keyboard and electronics units removed from the case
AMPLIFIER BOX OF THE FELD-HELL MACHINE
Fig. 4: front of the electronics box of the Feld-Hell machine
Fig. 5: top of the electronics box
(the four vacuum tubes can be pulled out, without opening the box)
Fig. 6: top of the electronics box - vacuum tubes pulled out
Fig. 7: rear of the electronics box - cover removed
(note that all the wires/signals are numbered on the circuit board; all components have a sticker with a number)
Fig. 8: left-hand side of the electronics box with connectors from motor-generator and base-module
Fig. 9: top-view of inside of the electronics box - rear cover and module with circuit card and vacuum tubes removed
Fig. 10: top-view of inside of the electronics box - rear cover and module with circuit card and vacuum tubes removed
Fig. 12: rear-view of inside of the electronics box
Fig. 13: the die-cast box, all components removed
Fig. 14: bottom-view of the circuit card & vacuum tubes module
Fig. 15: front-view of the circuit card & vacuum tubes module
Fig. 16: left & right side-view of the circuit card & vacuum tubes module
KEYBOARD AND CHARACTER-DRUM OF THE FELD-HELL MACHINE
Fig. 17: the keyboard/character-drum module
Fig. 18: bottom of the keyboard - 3-pole connector to the base-module in lower right-hand corner
Fig. 19: left-hand side of the keyboard/character-drum module with gear that mates with the gear-box
Fig. 20: rear-view of the keyboard/character-drum module
Fig. 21: keyboard/character-drum module - character-drum removed
Fig. 22: the character-drum
MOTOR-GENERATOR OF THE FELD-HELL MACHINE
Fig. 23: cross-section of the Feld-Hell motor-generator
Fig. 24: the single-rotor motor-generator and the corresponding cross-section drawing
Fig. 25: top of the motor-generator - speed-adjustment cap removed
(the flat yellow capacitor is a modern replacement)
Fig. 26: speed-regulator disk with contacts (normal & overspeed) and EMI-supression components
(the flat yellow capacitor is a modern replacement)
Fig. 27: looking down into the top of the motor-generator - cap and speed-regulatro contact disk removed
Fig. 28: the centrifugal part of the speed-regulator
Fig. 29: side-view of the centrifugal part of the speed regulator
(as rpm increases, the weight (far left) moves outward, the steel ball at the center moves up, and actuates the contacts of the disk above it)
Fig. 30: looking down into the top of the motor-generator - speed regulator removed, motor shaft visible
(the two electrolytic capacitors at the lower right-hand are are modern replacements)
Fig. 31: the single rotor of the motor-generator - separate commutators for the motor and the generator
Fig. 32: looking down into the motor-generator - speed-regulator, carbon-brushes, and rotor removed
Fig. 33: bottom of the motor-generator with pin-coupling (left) and top of the gear-box (right)
(note the thin red alignment markings (aid for re-assembly))
THE BASE-MODULE OF THE FELD-HELL MACHINE
The base-module contains the gear-box and the two drawers for rolls of paper tape, ansd is the mounting platform for the motor-generator,the keyboard/character-drum module, and houses the two-position locking mechanism for the carrying case.
Fig. 34: front of the base-module - printer module attached
Fig. 35: rear of the base-module
(the 3-pin connector on the far left connects to the keyboard/character-drum module)
Fig. 36: bottom of the base-module
(the spring-loaded lever on the left is for locking the base module in two positions in the carrying case)
Fig. 37: bottom of the base-module - covers and locking-lever removed
(note the bossed "T typ 58" at the lower left-hand corner of the casting and the Siemens-Halske logo at the top of the paper tray)
Fig. 38: front of the base-mdoule - paper tape drawers partially pulled out
GEAR-BOX OF THE FELD-HELL MACHINE
The motor-generator is mounted on top of the gear-box, and has three output shafts: two on the front (printer spindle and paper tape transportation), and one on the right (character-drum).
Fig. 39: the gear-box
(motor-generator, pin-coupling, printer module, keyboard & character-drum removed)
Fig. 40: schematic top-view of the gear-box - ball-bearing at the center is for the vertically installed input shaft
Fig. 41: the gear-train of the Feld-Hell machine - ball bearings removed
Fig. 42: the gear-train of the Feld-Hell machine - ball bearings removed
In case you wonder how I took the above two photos of the gearing - it was not easy: I suspended all five shafts like marionettes, with mono-filament fishing line.
Fig. 43: the gear shafts, suspended for taking photos
Fig. 44: pin-coupling between the motor-generator shaft (top) and input shaft of the gear-box (bottom)
Fig. 45: the large steel gear on this output-shaft of the gear-box meshes with the large gear on the character-drum
Fig. 46: the drive shaft to the printer spindle
(the greenish socket for the ball bearing is mounted into the front of the gear box)
Fig. 47: driver shaft of the paper tape transportation
Fig. 48: rear-view of the gear-box, cover removed
(the horizontal shaft is the output to the character-drum; bottom-right: timing/interrupter cam-wheel for the pause-character)
Fig. 49: bottom-view of thegear-box;main (vertically installed) shaft with bottom ball bearing, spindle & paper transportation shaft
(front of the unit is on the right-hand side)
Fig. 50: several types of gear (left) and my great-grandfather with his gear driven (chainless!) bicyle (ca. 1914)
(spur gear (1, 2), bevel gear (3), helical gears (4), worm-gear (5) and pinion ( 6))
PRINTER-MODULE OF THE FELD-HELL MACHINE
Fig. 51: the printer-module (left) and the front of the base-module without the printer
Fig. 52: front and rear of the printer-module
Fig. 53: bottom & front of the printer-module, cover removed
Fig. 54: the printer solenoid (electro-magnet) with hammer armature
Fig. 55: left-hand side of the printer-module and the spindle holder
(note the HELL marking on the spindle holder)
Fig. 56: the two-start Hell printer spindle
Fig. 57: top-view of the printer module, with paper tape
Fig. 58: felt ink roller with holder and two spares
TIPS FOR TAKING GOOD PHOTOS OF EQUIPMENT
Good photos of equipment are clear, evenly exposed, have true color, are undistorted (barrel, skew, fish eye), and have no shadows on the equipment. If you want to take good photos of equipment, there are some simple rules to keep in mind...
- Make sure that the camera is not moving at all when taking the photo:
- always use a tripod
- always use timer-release
- Equipment typically has parts that stick out (knobs, handles, ...). Shadows in your photo do not look nice, so only use diffuse lighting!
- never use flash
- never take photos in direct sunlight
- best is outside on a very cloudy day
- it is OK to have shadows that are not on the equipment, as they can be edited away afterwards
- The color of all (!!) objects anywhere near the equipment (including the background and the surface underneath the equipment!!!!) are reflected on the equipment. This can not be removed from the image afterwards!
- Use a non-glossy neutral background (white/grey/beige or darker color similar to that of the equipment) around & underneath the equipment. Never use bright, contrasting colors (neon green, orange, red,...).
- We are not going for artistic effects, so large depth-of-field is preferred ( = the entire object is in focus, at all distances from the camera). This can be achieved by taking the picture form a greater distance (with zoom, if required), or - if your camera has a manual mode - select a small aperture and/or a longer exposure time.
- Fill the image with the object of interest, but for depth-of-field reasons (and to avoid so-called "fisheye" distortion), use zoom rather than getting very close top the object. This also minizes keystoning and other undesirable perspective effects.
- With a digital camera, only use optical zoom, never digital zoom.
- If the equipment, or any of its visible parts, has a shiny (reflective) surface, then make sure that no undesirable objects are visible in the reflection.
- Use image/photo editing software to remove all background and objects that are not part of the equipment (sorry, but Photoshop etc. are not particularly suitable for this), and to correct distortions (fisheye, skew, perspective,...).