Electronic Countermeasures
This is a detailed guide to the effective use of ECM, the Caldari form of electronic warfare. Refer to the University's EWar 101 Guide for the very basics necessary to function as a rookie ECM pilot.
You should read this guide if:
- You are flying Caldari ships (other race's ships offer little to no benefit to ECM)
- You love to annoy enemies
- You want to fly with groups of people
- You want to use ECM drones or Counter ECM (ECCM)
- You are just curious about the mechanics of ECM
What is ECM?
ECM stands for Electronic Counter Measures and is also often referred to as jamming. ECM modules allow you to cause a targeted ship to lose any targets it has locked already, and lose its ability to target anything for 20 seconds (or longer if you happen to get more than one successful jam in a row). During combat this means the affected ship cannot shoot you or any of your fleet mates. This also includes other effects which require targeting, e.g Webbing, Scrambling and their ability to use Ewar. Your target will still be able to use modules which don't require a target such as Smartbombs or other area effect weapons, and they may also use FoF missiles. ECM is generally regarded as the most effective Electronic Warfare technique.
Who should use ECM?
ECM is the preferred EWAR technique for pilots training in Caldari ships.
There are 8 Caldari ships which give specific bonuses to ECM:
Tech 1 ships
- Griffin (Caldari frigate):
- Caldari Frigate Skill Bonus
- 15% bonus to ECM Target Jammer strength
- 10% bonus to ECM Target Jammers' capacitor need per level.
- Caldari Frigate Skill Bonus
- Blackbird (Caldari cruiser):
- Caldari Cruiser Skill Bonus
- 15% bonus to ECM Target Jammer strength per level
- 10% bonus to ECM Target Jammer optimal range and falloff per level.
- Caldari Cruiser Skill Bonus
- Scorpion (Caldari battleship): * Please note that the Navy Issue Scorpion has no bonuses towards ECM
- Caldari Battleship Skill Bonus
- 15% bonus to ECM Target Jammer strength per level
- 20% bonus to ECM Target Jammer optimal and falloff range per level
- 20% Bonus to ECM Burst Range per level
- Caldari Battleship Skill Bonus
Tech 2 ships
- Kitsune (Caldari Electronic Attack Frigate):
- Caldari Frigate Skill Bonus
- 20% bonus to ECM target jammer strength and 10% reduction in ECM target jammers' capacitor need per level
- Electronic Attack Ships Skill Bonus
- 10% bonus to ECM target jammer optimal range and 5% bonus to capacitor capacity per level
- Caldari Frigate Skill Bonus
- Rook (Caldari Recon ship):
- Caldari Cruiser Skill Bonus
- 10% Bonus to ECM Target Jammer capacitor use per level
- Recon Ships Skill Bonus:
- 30% Bonus to ECM Target Jammer strength per level
- Caldari Cruiser Skill Bonus
- Falcon(Caldari Recon ship):
- Caldari Cruiser Skill Bonus
- 10% Bonus to ECM Target Jammer capacitor use per level
- Recon Ships Skill Bonus
- 30% bonus to ECM Target Jammer strength per level
- Caldari Cruiser Skill Bonus
- Widow (Caldari Black ops):
- Black Ops Skill Bonus
- 30% bonus to ECM target jammer strength
- Black Ops Skill Bonus
Tech 3 ships
- Tengu (Caldari Strategic cruiser):
- Obfuscation Manifold subsystem
- 10% bonus to ECM target jammer optimal range per level.
- Rifling Launcher Pattern subsystem
- 10% bonus to ECM target jammer strength per level
- Obfuscation Manifold subsystem
ECM Modules
There are 3 main types of ECM modules:
- ECM Multispectral Jammers - These modules are reasonably effective on all targets with a high capacitor cost. These modules have a significantly lower range than racial jammers.
- ECM Racial Jammers - These modules are more effective against a single race's ships, and much less effective than a Multispectral against the other three. They have a longer range and lower capacitor cost than multispectral jammer modules.
- ECM Burst Jammers - These modules will cause all ships within a certain range of your ship to be jammed. You do not need to be targeting anyone to use a Burst module. Burst modules consume a high amount of capacitor and are generally only used on Battleships. REMEMBER: The ECM burst modules will get you concorded when used in high sec and they will also jam your fellow fleet members if used in close proximity. These modules should only be used outside of high sec, and when you know what you are doing!!!
Low slots:
- Signal Distortion Amplifiers - These low slot modules increase the strength and range of your jammers
Rigs:
(Remember that during wartime University pilots cannot fly Tech 1 ships smaller than Battlecruisers with rigs.)
- Particle Dispersion Augmentors - These rigs also increase the strength of your jammers
- Particle Dispersion Projectors - These rigs increase the range of your jammers
Drones:
ECM drones are useful for any pilot but are unaffected by any ECM skills/ship bonuses.
- Hornet EC-300 - Light drone - Has a strength of 1 for all sensor types
- Vespa EC-600 - Medium drone - Has a strength of 1.5 for all sensor types
- Wasp EC-900 - Heavy drone - Has a strength of 2 for all sensor types
It is tough to choose between fitting several multispectral jammers or a variety of race specific jammers. If you know the type of fight you are heading towards you can make a tactical decision (or the fleet commander might make this decision before you head out).
- The practice of fitting one of each racial ECM is known as fitting a rainbow configuration. Most UNI fleet commanders expect you to fit a rainbow configuration, and if you are ever in doubt about what kind of jammers to fit, you should go with a rainbow configuration.
- If you plan on fighting and jamming multiple ships then you should fit racial jammers. This will allow you as the ECM pilot to target a few different ships and have a high chance of locking them all down (i.e. jamming them).
- If you plan on fighting individual ships (or very small gangs), and don't know what type of ship you will be fighting ahead of time then ECM will be more affective with multispectral jammers since you could activate more than one on a single target and have a higher chance of locking them down.
- If you have intelligence about the ships being flown by your enemy you can have your pilots fit multiple jammers which match the race type of your target ship(s). It can be useful to carry a spare set of one of each of the four racial jammers in an ECM ship's hold, for refitting on the fly.
Using your ECM Modules
The race-specific modules are not named in a way that makes it obvious what race of ships they're effective against. I have compiled a series of images to help you make a quick decision when in the heat of battle. Remember that each race's ship's all have the same colour background in the portrait image you see when you have them targeted.
- Amarr - Radar (yellow-coloured jammers)
- Caldari - Gravimetric (blue-coloured jammers)
- Gallente - Magnetometric (green-coloured jammers)
- Minmatar - Ladar (red-coloured jammers)
Your Target Ship | Which Racial Jammer to use |
---|---|
Amarr | a.k.a "White noise" |
Caldari | a.k.a "Spatial Destablizer" |
Gallente | a.k.a "Ion Field" |
Minmatar | a.k.a "Phase Inverter" |
If you can remember these colour match ups then you will remember exactly which module to activate on a ship you are targeting. If you don't think you will remember this you could use Multispectral ECM modules so you never have to remember.
When you get a successful jam you will know because a 4th bar will be added to the target (under the structure bar) which shows you how long the jam has until it ends. See the image below.
Skills to improve ECM
There are a few skills which will improve your abilities as an ECM pilot:
- Caldari Frigate/Cruiser/Battleship - Skills for the specific types of ship you are flying will give you the greatest improvement in ECM effectiveness (see the ship bonuses in the ship section above)
- Signal Dispersion - Increases your jam strength by 5% per level. This skill requires Electronics 5. If you have decided that you really enjoy being an EWAR pilot this is a great skill to work towards, but it certainly isn't required to have fun flying ECM in fleets.
- Long Distance Jamming - Increases the optimal range of your ECM modules by 10% per level. Requires Electronics 4. Another great skill to work towards if you enjoy EWAR.
- Electronic Warfare - Required to use ECM mods, reduces their cap usage by 5% per level.
- Frequency Modulation - Increases the falloff distance (this will be explained later) of your ECM mods.
- Electronic Superiority Rigging - This will allow you to use the ECM rigs (Requires Jury rigging III)
Fitting Fleet Blackbirds
The Blackbird cruiser is the most common ECM ship in University fleets, though new ECM pilots often begin with the Griffin (you can find a Griffin fitting suggestion in the corporation fittings section of your saved fittings). This section discusses possible fleet fittings for a Blackbird.
High slots (4)
Weapons should be fit after all other modules -- dealing damage is not your main concern -- and they should be weapons which consume no capacitor. For most Caldari pilots this makes missile launchers ideal: Heavy Missile Launchers have a nice long range to match your ECM ranges, Assault Missile Launchers have a medium range and can really hurt enemy frigates; Heavy Assault Missile Launchers are a pain to fit and have very short ranges.
Energy neutralizers can be a great addition but remember they use a lot of cap (when in doubt, don't fit them). Other options include a salvager in your spare high slot to clean up wrecks after fighting, or a medium remote armor repairer to help patch allies up after fighting (but not during battle, when your attention, and your capacitor, should be running your ECM).
Mid slots (6)
Standard Blackbird fits mount four ECM modules, either 4 multispectrals or 1 of each racial ECM module (a.k.a 'Rainbow ECM'). It is strongly recommended to go with the rainbow since despite the lower chance of jamming a single target, in fights where it really matters where you have multiple hostiles, you can generally find enough different racial targets to make your rainbow more effective, at a lower cap cost and longer range.
This leaves two further midslots free. It is often useful to have a propulsion module, most commonly a Microwarpdrive, to help you move around the battlefield and control range to some extent. Remember that a MWD reduces your total cap when you fit it, and uses a lot of cap when running -- pulse it, don't leave it on. MWDs are indispensible in nullsec fleets, where they can help you burn out of warp disruption bubbles.
A Sensor Booster will increase your scan resolution (helping you lock enemies quicker) or your targeting range. You can use a Scan Resolution script to get even faster locking with lower targeting range, or a Targeting Range script to get even longer targeting range with a penalty to your locking time. If you fit a Sensor Booster you should load one script (probably Scan Resolution) and carry the other one in your cargo for quick swapping if necessary.
There are other options: a Large Shield Extender can give you a bit more buffer to survive in time to warp out if you're primaried, without slowing you down like an armor plate would; a fifth jammer helps you cause even more mayhem at the cost of the utility module you could otherwise have fitted in its place; if the enemy often field their own ECM ships, you may want to fit an ECCM module.
There is no one perfect fit that will work in all situations, and with experience you will be able to more accurately guess which kind of fit will suit a particular fleet. You can't go far wrong with four racial jammers, a Sensor Booster and a MWD.
Low slots (2)
Usually a fleet Blackbird will fit two Signal Distortion Amplifiers. However, some pilots like to fit one SDA and one 1600mm armor plate (which requires Hull Upgrades 3). A 1600mm armor plate gives you considerably more buffer, giving you a better chance of warping out if you're primaried, though the plate will make you slower and less agile, and the loss of one SDA cuts your jamming range and strength.
EFT Fitting
This is an example EFT fitting based on the above, using vanilla Tech 1 Meta 0 modules and no rigs: you can copy the following text to import it into EFT.
[Blackbird, Basic Fleet BB] Signal Distortion Amplifier I Signal Distortion Amplifier I ECM - Spatial Destabilizer I ECM - Phase Inverter I ECM - Ion Field Projector I ECM - White Noise Generator I Sensor Booster I, Scan Resolution 10MN MicroWarpdrive I Heavy Missile Launcher I, Havoc Heavy Missile Heavy Missile Launcher I, Havoc Heavy Missile Heavy Missile Launcher I, Havoc Heavy Missile Salvager I
This fit does not have rigs since University pilots may not fly rigged Tech 1 ships smaller than battlecruisers in wartime.
You will want to carry one or two spares of each kind of jammer in your hold for quick refits if your fleet gets intelligence about the enemy's ships.
How does ECM work?
Every ship in the game has a base sensor strength and this sensor is always of a known type (Gravimetric, Ladar, Radar, Magenetometric). Your chance to jam a target is based on this equation:
Chance to Jam = ( Your ECM Strength / Target's Sensor Strength ) * 100%
And if you use multiple jammers:
Chance to Jam = (1 -(1 - Your ECM Strength / Target's Sensor Strength ) ^ The number of jammers of this strength)*100%
Note that when calculating the chance to jam a single target using a rainbow fit, the above formula must be modified, considering that a rainbow fit will have different jam strengths, per racial jammer, dependent on the target race type. As an example, jamming a ladar sensor ship:
Chance to Jam = (1 -(1 - Ladar Jammer Strength / Target's Sensor Strength ) x (1 - Ladar Jam Strength on non Ladar Jammers / Target's Sensor Strength )^3
(the little ^ symbol means "to the power of")
So let's use that equation in an example:
Scenario 1
Say your fleet is flying around and you come across a scary Caldari Raven. You throw on your sensor booster and get a target lock on him really fast. You are lucky (or unlucky!!) that this Raven is within 50km and inside your optimal range of your ECM modules. You see the Raven start to get a target lock on you (and you begin to sweat a little)
You make a quick decision:
Caldari | Gravimetric jammer |
What are your chances that you won't get turned into a fine mist?
Let's assume that the Raven has no modules active that increase his sensor strength and therefore has 22 points of Gravimetric sensor strength.
Let's assume you are flying the Blackbird above with 2 Signal Distortion Amplifiers and no skills to increase your jamming strength; you also only have Caldari Cruisers II (you are a noob) and you have all Tech 1 Meta 1 jammers.
First let's calculate your jammer strength:
The "ECM - Spatial Destablizer I" has a Gravimetric strength of 3
This will be improved by the Blackbird's ship bonuses and by the Signal Distortion Amplifiers.
- Caldari Cruiser II -> 30% ECM jammer strength for a Blackbird which will add : 0.9 strength
- Signal Distortion Amplifier I (2 of them means one will have the stacking penalty (87% effective)) -> 9.35% ECM jammer strength : 0.28 strength
So in total we will have 4.18 jammer strength (uh oh)
Chance to jam = (4.18 / 22) * 100%
Chance to jam = ~ 19%
So you have a small chance to survive and you will probably be turned into goo! Oh well.. for the fun of it let us work out the chance of the NON-racial jammers on him (hey, every little bit helps right?)
Lets assume you have 1 of each racial jammer. Their jamming strength when miss matched with the target is 1. With our modifiers that gives us a strength of 1.39 jamming strength
Chance to jam = (1.39/22) * 100%
Chance to jam = ~ 6%
If you activate all you get ~32% (please check my maths)
So that is pretty bad, but it is still something!
Scenario 2
Now lets assume we run into the same Raven but this time we are rolling with 4 Multispectral jammers. We get him targeted and we throw all of our jammers at once.
Ok, the Meta 1 Multispectral has a jammer strength of: 2 With all of our bonuses the strength comes up to: 2.78
Chance to Jam = (1 -(1 - 2.78 / 22 ) ^ 4)*100%
Chance to Jam = ~ 42%
or ~13% per module
Ok this is a little better...
Scenario 3
Ok now let's assume we were going to hunt a known target, a Raven! We are so sure this is the only thing we will run into that we put 4 racial jammers on our Blackbird and let out an evil giggle.
We found above that using a racial jammer gives us a gravimetric strength of 4.18 (per module)
Chance to Jam = (1 -(1 - 4.18 / 22 ) ^ 4)*100%
Chance to Jam = ~ 57%
So you can see you have an advantage when you know your target type and fit appropriately. But this advantage isn't that great and most of the time you can fit rainbow (one of each racial) or multispectrals.
Scenario 4
Ok let's assume you have a little bit of money and can afford to use Meta 4 jamming modules (BZ-5 Neutralizing Spatial Destablizer ECM) and you can fit two Medium Particle Dispersion Augmentors (rigs which would not be allowed on cruisers in wartime in the University). Let's also assume that you have spent ~5-6 days training up Caldari Cruiser skill to IV and you have spent 2 weeks training Signal Dispersion to level 4 (requires Electronics 5 and Electronic Warfare. This may take 2-3 weeks to acquire).
let's assume you fit a rainbow fit (one of each racial jammer) and you came up against the same Raven.
Your new shiny racial jammer has a base strength of 3.6 (not that much better than meta 0)
- Caldari Cruiser IV -> 60% (and 40% range)
- Signal Dispersion IV -> 20%
- Signal Distortion Amplifier II x 2 -> 18.7%
- Medium Particle Dispersion Augmentor x2 -> 18.7% (10% for first, 8.7% for second)
This leads to a large 8.98 strength jam. (using EFT to find this number)
Chance to jam = ( 8.98 / 22 ) * 100% = 40% with a single module
You can do the maths to work out how well 4x multispecs would work in this setup.
Summary of scenarios
Scenario | Modules fitted | Chance of jamming | Optimal range of fit (Cruisers II) | Capacitor usage | Advantages | Disadvantages |
---|---|---|---|---|---|---|
1 | Single Racial module (tech 1) | 32% (19% with single module) | 38km with 35km Falloff | 2.4GJ/sec per module (9.6GJ/sec) | Cheap! Long range | Low chance to jam |
2 | 4 Multi spectral modules (tech 1) | 42% | 26km with 23km Falloff | 3.6GJ/sec per module (14.4GJ/sec) | Cheap and High chance to jam single target | Very low range. Within range of most weapons |
3 | 4 Racial modules (tech 1) | 57% | 38km with 35km Falloff | 2.4GJ/sec per module (9.6GJ/sec) | High chance to jam the right type | Not versatile, only effective against single race |
4 | High quality Racial with rigs (tech 1 meta 4) | 40% (single module) | 70-80km with 70-80k Falloff | 2.4GJ/sec (single module) | High chance to jam at low cap cost | Expensive(*), requires high skills |
(*) Note: With meta 3 modules this fit is almost as powerful but a lot cheaper.
Falloff and Optimal range
Remember to set your orbit range correctly with regards to the types of ECM modules you are using:
- Multispectral modules have an optimal around 18km to 40km depending on skills with a falloff of 20-30km
- Racial modules have an optimal around 40km -> 50km depending on skills with a falloff of 40-50km
The Blackbird, Scorpion and Kitsune (but not the Griffin, Rook and Falcon) have bonuses to ECM range based on your ship command skill which will modify these values. Tech 2 or Meta 4 jammers fitted in a Blackbird fitted with two T2 or Meta 4 Signal Distortion Amplifiers and piloted by a character with Frequency Modulation, Long Range Jamming and Caldari Cruiser all at level IV will have an optimal of 75km and a falloff of 70km.
The above scenarios are correct when your target is between you and your optimal range. When your target is past this optimal range it affects the chance that you will jam them. This works much in the same way weapon's fall off ranges work.
- When your target is at optimal you will get the percentages found in the scenarios above.
- When your target is at optimal + falloff you have a 50% chance to have the above chances
- When your target is at optimal + 2 x falloff you have a 0% chance of jamming them
Here is an example: let's assume your ECM module has a 50km range and has a 40km falloff. When your target is within optimal range you have a 20% chance to jam them per cycle of your modules.
- If your target is 50km away you will have a 20% chance to jam them
- If your target is 90km away (50km + 40km) you will now have 10% chance to jam them (50% of 20%)
- If your target is 130km away (50km + 40km + 40km) you now have a 0% chance to jam them
Without any skills in targeting a Black Bird has a 75km targeting range and 112.5km with a targeting script in your sensor booster. So the rule of thumb for a new player should be: If you can target them, try to jam them!!
Countering ECM
Now you should understand exactly what ECM is and how it works within Eve. How is it countered? In order to make it harder for ECM modules to jam you you simply need to increase your sensor strength. You can do this in a variety of ways:
- Get a bigger ship. Bigger, more powerful ships have naturally larger sensor strength: e.g a Merlin (frigate) has a sensor strength of 11 while a Raven (battleship) has a sensor strength of 22.
- ECCM modules (mid slot) - These active modules can be used to increase the strength of a specific type of sensor (Gravimetric, Radar, Ladar, Magnetometric) by a percentage (80% from a Tech 1 Meta 0 ECCM module). Since they give a percentage bonus, they give larger ships much bigger bonuses than smaller ships. When activated they use a little bit of capacitor and make a distinctive mottled visual effect appear around the ship running them in space.
- Sensor Backup Arrays (low slot) - These modules are similar to ECCM modules but use low slots and give smaller bonuses (40% from a Tech 1 Meta 0 SBA).
- ECCM Projectors - These allow other people to remotely project ECCM support on to your ship. A Tech 1 Meta 0 ECCM Projector increases your sensor strength by 100%.
Flying ECM: Targets
Unless you only have one or two enemies, judging which enemy you should try to jam is an important decision. Your Fleet Commander may tell you to jam a particular target or even appoint an ewar target caller, in which case you should obviously follow their orders. However, most FCs, most of the time, will not issue specific orders for their ECM ships, leaving the decision to you.
Often, particularly when you're in a large fleet, the primary target called by the FC for the damage-dealers is not the best ship to jam, since hopefully it will die soon anyway. Instead you should quickly look at what the enemy have and find some good targets for ECM.
If there are other ECM pilots in your fleet it can be useful to coordinate with them so that you don't waste time jamming the same target several times over. In a small fleet you might report your jams textually in the fleet chat channel, or even over TS if the FC is running the fleet with an open TS channel. In a large fleet you could try setting up a separate ewar chat channel for ewar pilots.
Here are some ships that often make good ECM targets.
Logistics ships
Logistics ships are T2 cruisers which can rapidly repair their allies' shields or armor. With sensor strengths ranging from 17 to 22 they aren't the easiest ships to jam, but if you do jam one it won't be able to heal the rest of the enemy gang for twenty seconds. Some gangs depend mostly on their logistics ship(s) for their tank, so this can be a battle-changing move.
The four logistics ships are the Amarr Guardian, Caldari Basilisk, Gallente Oneiros and Minmatar Scimitar.
RR battleships
A remote-repping battleship gang is a group of battleships which tank by repairing each other with repairers in their spare high slots (a tactic also referred to as spider tanking). This means that, much like logistics ships, they're vulnerable to jamming. Note that RR battleship fits often include an ECCM module precisely because of this weakness, so don't expect them to be easily jammed.
The Gallente Dominix is a particularly high priority ECM target in an enemy RR battleship fleet: it usually does damage using drones, which means all or most of its highslots can be dedicated to remote repairers.
Ewar
If the enemy have their own ewar ships it can be useful to jam them. This goes especially for enemy ECM ships. Equally, of course, electronic warfare ships and especially ECM ships have high sensor strengths for their hull size.
Damage dealers
If you don't see any stand-out targets, like logistics ships, jamming enemy damage-dealers is probably a safe decision. This usually means battleships and battlecruisers but the enemy might field a fast-moving gang of smaller ships. The T2 cruiser-sized heavy assault cruisers and frigate-sized assault ships are noteworthy smaller damage-dealers, and they don't have very high sensor strengths.
If you're flying a Blackbird, Scorpion or Kitsune you will have a long enough range that you will be one of the few ships in the fleet that might be able to counter enemy snipers. With good ECM range skills, the Blackbird and Kitsune should have a decent chance to jam sniper HACs, and the Scorpion should have a decent chance to jam sniper battleships. (This is where a Targeting Range script can come in useful if you fitted a Sensor Booster.)
Flying ECM: Advanced tactics
Never activate all of your ECM modules on a target at the same time
If you have some time (you are not about to die) you can gain a large advantage if you do not active all of your ECM modules on a target.
Let's assume there are two targets attacking you and your friends. Immediately you target both of them and decide you will turn on two multispectral jammers for each. One of the targets gets lucky and avoids both of the jams and the other target gets jammed from your first ECM module. The lucky enemy (that didn't get jammed) then happily targets you and blows you up! Ouch.
Now that is an unpleasant scenario we might have avoided.
This time we decide to turn on one module per target. Target 1 is lucky and doesnt get jammed. Target 2 is unlucky and we jam them.
At this point we have 2 more modules to work with. We attempt to jam target number 1 with another module and he is AGAIN lucky (just like in the first example) We finally turn a third module onto target 1 and this time we jam him and live to fight another day!
You can see with this example that it is in your best interest to use as little number of jammers on your targets until you get an actual jam. Remember that the activation time of ECM modules is 20 seconds, which is the same length of time that the jam will last.
Jamming and aggression
Sometimes it is unwise to jam someone who is trying to play docking games with you. To win at docking games you sometimes need to rely on the fact that when your target shoots something he starts a so-called aggression timer and cannot dock for 60 seconds, hopefully giving you time to kill him. If you happen to get a jam off on a person playing docking games he has twenty seconds during which he cannot target anyone and thus gets closer to being able to dock. You generally want someone playing docking games to be trying to shoot someone.
Aggression timers also prevent pilots from jumping through stargates, and so the same principle applies if you want to keep someone aggressed on one side of a stargate.
Overheating
Like many other modules, ECM jammers can be overheated. Overheating an ECM jammer increases its jamming strength. This can be very useful but, as with ECM in general, since it only increases your chance to jam, it's still a gamble: overheated jammers can fail to jam their targets, and when that happens you still have the heat damage from overheating. And, just like any other module that can be overheated, if you overheat too much you'll burn your jammers out. You may find it useful to persuade a fellow unista to be your practice dummy, letting you practice overheating and get a feel for how long you can heat your jammers before you do it in battle.
If in doubt, don't overheat. Better to miss a few jams than to miss all the jams after the first minute because you burned your midslots out.