Editor's Note: These rules are a variant only, and are Unofficial.
In recent years, the proliferation of vehicular weaponry has only been matched by the increasing availability of vehicular electronics systems. These wonders of the modern age (targeting computers, radar detection and jamming systems, remote control and satellite communication rigs) can make or break the highway warrior of 2039. Yet these systems lack a certain flexibility. Why can't you "burn through" an opponent's radar jamming by using electronic countermeasures of your own?
Electronic warfare (EW) can be loosely defined as the observation and control of portions of the electromagnetic spectrum in order to confound your opponents. EW is customarily divided into two categories; active and passive. A radar detector is a passive system; so is StealthKote. Active systems transmit a signal of some sort: either one designed to "jam" or distort an enemy's signals, or a signal intended to somehow circumvent enemy jamming. Either form of EW can have a tremendous effect on a battle; in combination, they are devastating. Imagine an arena where your opponents are not allowed to talk to one another because their radios don't work. Of course, since it's your jamming, your radio is unimpaired.
When using these rules in a role-playing setting, bear in mind that barrage jammers such as the Bollix are illegal in many areas, typically around cities and airports. The equipment will sometimes be impounded outright (it may or may not be given back when you leave), or it may simply have to be registered with the local authorities.
In Car Wars, three types of systems are susceptible to the effects of EW: Radio communication of all sorts, including remote control links; radar, including missile guidance radar; and laser guidance rigs for vehicular weaponry, including targeting and infrared targeting lasers only. Larger lasers used to guide rockets cannot be interfered with, nor may they be used for target painting (see below). All EW functions are carried out at five-second intervals; at the beginning of the turn, just before speeds are set, all sides in the EW engagement roll to determine which side has control of the other for the next five turns, and to what degree. All EW combat is simultaneous. laser-related functions are the exception. Target painting requires a firing action, and laser-guidance countermeasures are resolved on a shot-by-shot basis.
The portion of the EM spectrum used for radio transmissions is quite vulnerable to electronic tampering. The most fundamental kind of radio EW is scrambling. A scrambled transmission is unintelligible to any listeners who do not have a similar scrambler set to the proper code. An eavesdropper would hear noise, and know the length of the transmission, but not its content. A scrambler may be purchased for any vehicular radio, portable radio or walkie-talkie, costing $600, no weight or space. A scrambled signal may also be decrypted, or interpreted, by a decoder ($1,000, no weight or space). The first message from a given scrambler or net of scramblers "heard" by a decoder may never be decrypted; the gadget has to have some data on the signal to work with. The scrambler users will not know they are being monitored. Remember, if you don't know the setting for your friend's scrambler, his transmissions will be so much noise; and there are far too many setting combinations to simply flip through them and hope to get lucky
Radio may also be jammed; this is an active function. In this case, jamming means distortion of your opponent's radio transmissions. There are two types of radio jamming: broad spectrum, or "barrage" jamming, which interferes with all signals in a certain area (even friendly ones), and narrow beam, or "point" jamming which only affects the other guy's signals. Both sorts of jamming have a base range of three miles; a barrage jam mer would affect all radio communication within three miles. A point jammer cannot be focussed on a target more than three miles away. Remote-control equipment is an exception to this. Because of the inherent encoded nature of RC transmissions, base range to intercept, jam or otherwise inconvenience such transmissions is only one mile.
Each type of jamming has its advantages and disadvantages. Barrage jamming is most effective against those who don't have EW equipment of their own, and it has the advantage of simplicity; just flick a switch and let 'er rip. The disadvantages are that it can be worked around ("burned through") by the right combination of equipment and skill, and it consumes more power than point jamming, since the jam is spread thin over the entire spectrum. Once a barrage jam is burned through, it is gone - any further attempts to jam from that equipment in that engagement will be countered automatically. Some duellists carry multiple barrage jammers to assure themselves of a constant jamming umbrella.Point jamming must be aimed just like a weapon; it can miss, but when it's on target it is much more difficult to burn through. Since it's concentrated on a tiny portion of the spectrum, it takes less power to be effective. Point jamming requires a new skill - Electronic Warfare - and one or more members of the vehicle crew will usually be dedicated to operating the EW equipment. Once the target of a point jam burns through the interference, the jamming equipment must be recalibrated, a process which requires five seconds, during which the EW systems operator may do nothing else.
The basic roll to hit with point jamming is 8+ on two dice, modified as follows:
+1 per level of EW skill. +1 per attempt after the first (up to +4). +2 if barrage and point are used on the same turn. -1 if under barrage jamming. -2 if using unattended point jamming. -3 if no EW skill.
All modifiers are cumulative.
Burning through an opponent's jamming is done with a roll "to hit" just like regular combat, modified by operator skill, sustained attempts, etc. The basic burnthrough roll is 8+ against barrage jams, or 10+ against point jamming, on two dice, modified as follows:
+1 per level of EW skill. +1 per attempt after the first (up to +4). +2 burning through your own barrage jam. -2 if burning through unnattended point jamming. -1 if under barrage jam. -1 if under point jam. -3 if no EW skill.
Again, all modifiers are cumulative.
Barrage Jammer - $2,000, 1 space, 100 lbs., 2 DR Sets up a barrage jam in a standard three-mile radius. No to-hit roll. Drains 2 power factors per minute of operation.
Point jammer - $2,000, no weight or space, to-hit 8. jams a specific set of target transmitters if it hits; one attempt is allowed every five seconds. The jammer should be attended by an operator; if it isn't, it suffers the "unattended" penalties above. May not be operated by a computer gunner. Drains 1 power factor per minute of operation.
Jam breaker - $2,000, one space, 50 lbs., 1 DR tohit 8 against barrage, 10 against point. If the to-hit roll is made, it breaks the jam. A broken point jam may not be re-established for five seconds. Drains one power factor per minute of operation. This device must be controlled by a human operator to be effective. Also gives range and bearing to the source of jamming once it burns through.
Radar and EW gear may be put in cargo space.
Radar EW is quite similar to radio EW. The main difference is range; the base range for intercepting, jamming or otherwise influencing a radar signal is one mile.
EW functions for radar are basically the same as they are for radio. Radar may be jammed, just like radio, and the jam may be burned through. Radar barrage jams operate exactly like radio barrage jams. Radar point jams are slightly different. Instead of looking for a particular signal and jamming it when it's found, the radar point jammer automatically interferes with radar impinging on the vehicle mounting the jammer (see Radar jammer, Uncle Albert's 2036 Catalog Update, p.23). If the jammer is not manned, roll a die. On a 1 to 4, go on with the t'>hit procedure. On a 5 or 6, the jammer is not functional. If the jammer is manned by someone with EW skill, there is no initial roll; proceed with the to-hit roll. The basic roll to hit with a radar point jam mer is 8 or better on 2 dice, modified by:
+1 per level of EW skill. +1 per attempt after the first (up to +4). +1 if barrage and point jamming are used in concert. -1 if jamming long-range radar. -2 if unattended. -3 if no EW skill.
All modifiers are cumulative.
Burning through an opponent's jam requires an 8 for barrage or 10 for point jams, modified thus:
+1 per level of EW skill. +1 per attempt after the first (up to +4). -1 if under barrage or point jamming. -3 if no EW skill.
All modifiers are cumulative. As with radio, once a point jam is burned through, another one may not be established for five seconds. Once a barrage jam is burned, it's gone.
Barrage jammer - $3,000, 100 lbs., 1 space, 2 DR Sets up a barrage jam in a 1-mile radius. No to-hit roll. Uses 2 power factors per minute of operation.
Point jammer - $3,000, no weight or space, to-hit 8. Jams any radar signals received by the vehicle, at the operator's discretion. The vehicle may not operate radar-guided weaponry (including ATADs and HARMs) of any kind while this is active. Drains 1 power factor per minute while active. (Note: These rules replace those for the radar jammer on p.23 of Uncle Al's 2036 Update)
Jam breaker - $3,000, 75 lbs., 1 space, 1 DR to hit 8 against barrage, 10 against point. Uses 1 power factor per minute.
Lasers are, inherently, very tough to jam. In fact, short of being out of line-of-sight, there really isn't any way to keep a laser from hitting you. However, one of the most useful functions of the laser in Car Wars is to guide rockets with deadly accuracy. Laser guidance is subject to jamming. Another function of the laser is target painting where laser light reflected from a target is used to judge the range with high accuracy. The following text will be concerned with targeting lasers Cr15) unless otherwise specified.
Everyone knows how a limpet beacon or beacon mine works, right? You toss it on the road (or stick it to a car), and laser- and radar-guided weaponry homes in on the beacon on a 1 to 2 on one die. Said weapons are also at +2 to hit the beacon.
A system mounted on an automobile can be much more sophisticated (and more expensive, but it's only money). A vehicular anti-laser system uses data on impinging targeting-laser beams taken from the sensors of the laser-reactive web (see Uncle Albert's 2038 Catalog Update, p.10) and feeds it to the jammer. The jammer then broadcasts laser light tuned to the pattern which the incoming rockets are homing on in order to force them to miss. Simple, right? The game effect:
Any TI-guided weapon's fire which hits a vehicle equipped with a laser jammer will miss on a 1 to 4 on one die. The system may also be set to affect laser-guided weapons fired at targets within or passing through a 4" radius around the vehicle; in this case, it's only effective on a 1 to 3. In order for the jammer to be effective, there must be a functional IR web on the side facing the incoming rockets; if there is no web, that side is unprotected.
For those who still prefer limpet beacons, they may be made more effective by adding a beacon tuner, which also receives input from the IR web. This device takes data on lasers impacting the webbed vehicle and feeds it to the limpet beacons (or beacon mines). When the beacon is subsequently deployed, it affects laser-guided rockets on a 1 to 3 rather than on a 1 or 2. Lasers may have their patterns changed between battles; this is a Trivial job for a mechanic.
The third and most interesting function that a targeting laser may perform is "target painting." Painting with a laser is essentially shining it on the target for about a second. The reflected light is then picked up by a sensor (usually on another vehicle) and fed to a targeting computer which computes the position and speed of the target very accurately. The data is then used to train the guns of the vehicle on the painted target, all in about 1/10th of a second. The painting procedure is as follows:
The painting vehicle must score a hit on the target with a targeting laser modified for target painting.
Any vehicle firing at the target (from the same arc of fire of the target which the painting laser is striking) for the rest of the turn receives the paint bonus (see below) to that fire, as long as it has an LR web sensor that is facing the target, and has a targeting computer linked to the web.
A vehicle may paint for itself, but it must have at least two crewmembers on board (one to paint and one to fire) since painting lasers may not be linked to other aimed weapons. A computer gunner can operate a painting laser.
In order to be effective for multiple turns, the target must be repainted (or "touched up") every turn.
A single laser may only paint one target per turn.
The benefit of painting is that range and speed modifiers to hit the painted target are cut in half, rounding in the target's favor; a -5 speed modifier would be a -3 for a painted vehicle. In order to receive these benefits, the firing vehicle must have a IR web on the side of the vehicle facing the painted target, and it must be linked to the firing weapons. It must also have at least a targeting computer (not a SWC of either flavor, or the base targeting system which comes with any vehicle). A single TI may be used to paint and guide rockets, but not on the same turn. A normal damage causing laser may not be used to paint, unless it's equipped with a laser switch.
Laser jammer - $3,500 (plus the cost of the IR web), 100 lbs., 1 space, 2 DR A vehicle using this item may not have top-mounted turrets or accessories of any kind. The laser jammer doesn't work if the jamming vehicle is under the influence of a paint spray or paint gun.
Beacon tuner - $1,000, 100 lbs., 1 space, 2 DR 10 shots, CPS $250, WPS 1. loaded cost $3,500, loaded weight 110 lbs. loaded magazine costs $2,550 and weighs 25 lbs. Tunes limpet beacons as described above, turns them on and drops them. May be set to drop one or two beacons at a time. Shows as a dropped solid for vehicle descriptions.
Painting laser - $1,000 modification for targeting lasers. Allows target painting as described above.
Laser switch - $1,000, no weight or space. Allows a laser to fire as any lower-powered model; a heavy laser may fire as a laser, medium laser, light laser, or targeting laser with this item. To function as a targeting or painting laser, the weapon must still be tuned at the appropriate cost.