8-channels upgrades to 16 with optional A-B switch on the top.

• Larger sized head
• Some versions can scan

S500 head looks similar to a MASTR-II head
but comes in grey and not beige
 

• Non-scan
• Very small, nice in today's cars
• This simple, non-downloading "dumb" head is swappable with all Delta and RANGR models
• If you tend not to need scan, this may be a good choice.

S600 mini head
link to more S500 info via Hall Electronics
 

This is the only head with two rear control connectors as opposed to the normal three.  The control cable is unique to the S600 and the special cable must be used with this control head.  Conversely, the S600 head and cable combination works with all Delta and RANGR models.

Link to more info on cables & heads from Hall Electronics
http://www.hallelectronics.com/getech/n35.htm

BASIC SCAN HEADS

16-channels standard & upgrades to 32 with optional factory A-B mode button.  To use 32 channels, a 2nd EEPROM baby board must be installed into the radio drawer.

• A non-downloading "dumb" control head usable with all Delta and RANGR models.
• Not frequency sensitive and is easily swappable to different radios
• With front programmable  scan and priority
• If you have identified the 16 or 32 freqs that you will need and if you want to scan, this fairly low-cost head may be a great upgrade choice !
• ONE GOTCHA!
  Note that you cannot use a basic S600 cable on any other head including the S550 shown here.  The S550 head will work with just about any other control cable EXCEPT for the basic S600 as that cable uses two connectors.  All other heads use three connectors.

        S550 head
        often made in Taiwan

This setup for K1RJZ in a Chevy Trailblazer has a UHF Delta S550 control head on the left and a 6-meter Delta S550 control head on the right.  The UHF radio (left) cables can be swapped with a high-power 110W 2M radio drawer when needed as the cables and head are "dumb".  When a UHF radio is in service, a Yaesu FT90 on the console provides 2M access.

If you wish to swap-in various radios using the same cables, you must use a "dumb" control head like the S550 above.  Otherwise the fancier "downloading" control heads will try to reprogram your radios on the fly with very unexpected results!  Downloading control heads are also programmed to be frequency sensitive and are non-swappable to different bands.

S550 in a non-waterproof marine installation

Another zinger... The older version S550 heads required a backup battery for the scan memory and had a brown front escutcheon plate.  The newer S550 heads did not require the battery backup and had a grey front.  The S550 on the right is the newer version as shown by the grey color.  You can also identify the newer version by the fact that the LED's blink when entering a new channel to scan.  The older versions do not blink when entering a new channel into the scan memory.

Link to more info on cables & heads from Hall Electronics
http://www.hallelectronics.com/getech/n35.htm

• Downloading with scan
• More weatherproof for use on motorcycles and firetrucks
• Has alpha numeric display
• Can be more challenging to program

S825 head
Link to more info via Hall Electronics

• S700 info pending

picture and info still pending

S700 head

The key concepts of the 950/990 family heads shown below:

• Think of 950/990 head as a fileserver that is used to quickly download many bandplans into one radio but one at a time.  The frequency bandplans are called "modes" in GE parlance.  With the non-downloading heads (above), the EEPROM data in the radio does not change.  With a 950/990 head, the same EEPROM in the radio becomes an internal dynamic memory cache waiting to receive the latest frequency download from the head.
• You can use one 950/990 head as test gear-type storage to program other radios with non-downloading heads like the S500, S550 and S600
• If you have one set of cables in your car but plug-in radios for 10M, 6M, 2M and 440, you will need to have one matching 950/990 for each radio. This is not the case with  the non-downloading heads such as the S550 and S600 as one simpler head will work with many different models. 
• 950/990 heads as programmed must also stay within the same family meaning RANGRS with RANGRS and Deltas with Deltas. 
• Be careful:  As soon as you plug in and power-up a 950/990 head, the old freq plan in your radio is gone!  Jumpers can prevent this but be sure to jumper both the radio and head as they will loudly complain until the downloading conflict is resolved at both ends (radio and head). 
• The small front-facing panel requires no "lookdown" view as with some other Delta control heads like the S550.  With luck, it might even fit into some dash consoles.
• Unlike the rare 2212 EEPROM chip used in the radio drawers, the EEPROM used in this head is very common.  This means that one can easily purchase any of the many generic PROM programmers that are compatible with this chip.  This head can be used as a highly versatile piece of test gear if only used to program other radios!

• Buttons are not backlit but some versions have a lamp bar on top.
• Buttons are square
• GE logo in front

older S950 head
made in Lynchburg, VA

• with backlit buttons, no lamp bar
• Buttons are rectangular and not square.
• GE logo on top, not front

newer S990 head
made in Taiwan

No-one ever claimed that installing a rear-mounted radio was easy!  Perhaps the ultimate in a minimally-invasive, simple installation into to Toyota Tundra pickup was performed by W1JWZ.  The low-current receiver power was provided from an ignition-switched cigarette lighter.  The high-current transmitter power cable went directly to the vehicle battery via a 30 amp fuse.  A wooden block extended the small S600 control head to prevent any visible holes at vehicle resale time.  Most importantly, the large control cable was simply tucked under the floor mat on it's way to the radio drawer under the passenger seat.  Other hams may opt to route all cables under the main carpet for a less visible installation but at least you do have a choice.