The suggestions for fault finding below rely in your confidence that all is working perfectly before you leave base (see also Section 34, Pre-location equipment check). Nevertheless, faults can show up when least expected, and knowing how to work through the equipment in a logical order can help pin down the offending item, and may hopefully provide an instant solution, such as a switch incorrectly set. Sections 3, Camcorder: audio facilities; 4, Camcorder: track selection and magnetic recording; and 7, Camcorder: external facilities, are set out in a logical working and plugging order, and reference to these sections should help, in addition to the following suggestions and reminders.
Power
If everything appears to be dead, check your battery condition and connection. On some models, it is possible to accidentally knock and disconnect the battery when plugging cables at the rear of the camcorder. Batteries themselves can break internally (especially if dropped) and still appear perfectly all right from their external appearance. Some batteries have fuses, which may also ‘blow’ if too high a power drain is placed on the system (the most common example being the use of an on-camera light of too high a wattage). If the LCD display does not register characters, check/change the battery. The display probably also indicates the charge status of the battery as a guide (see also Section 7, Camcorder: external facilities) but you should carry several batteries as spares/back-ups in case of unforeseen problems (when other people lend a ‘helping hand’ it's all too easy for batteries to be left on location, in taxis, in coat pockets which are then left in a cloakroom, etc.).
If changing batteries proves ineffective, it is conceivable that the battery mounting plate may have developed a fault, and you will need to provide power via the 4-pin XLR socket, usually sited at the rear of the body. You can either use a mains adaptor which provides the correctly polarized 12 V DC for the camcorder, or an adaptor lead from a battery to the 4-pin XLR socket. If this too does not yield results, there is a cut-out designed to protect the camcorder itself from overload or power surge. It is frequently sited towards the rear of the body, and it may need to be reset.
If the equipment has separate replay functions, ensure it is switched to camcorder. On broadcast equipment, ensure that you have not selected the save (or cam) mode, when the tape will not be in contact with the heads, and no sound will be apparent on any monitoring facility.
Sound metering and monitoring
Assuming that the camcorder is powered, and that there is no sound signal apparent on either sound channel via your headphones or the meter display, first switch the track selection from the rear inputs to the on-camera (front) mic. Does the camera mic work, i.e. produce a signal? Switch to auto level to ensure the problem isn't an accidentally knocked level control.
This gives you a starting place, especially as you confirmed that it was working before you left base. At this point, we'll assume that the camera mic is producing a signal, so the fault lies somewhere on the input side of the selector switch. Do ensure that you can both hear the camera mic via your headphones and see its signal displayed via the metering.
If the metering is working, but your headphones are dead, with camera (front) mic selected to both tracks one and two, check:
Are they correctly plugged into the camcorder body? Pull the lead out and push it back, several times if necessary, to ensure it's properly seated in the socket. The jack socket itself may be faulty and not making proper/full contact with the plug.
Is the mini-jack damaged (the most common fault on headphones)? Waggle the lead close to the socket connection, to see if there is a cable or wiring fault. To be 100% sure, try the headphones in something else, for example, a personal stereo/cassette player.
Is the headphone lead damaged or broken at the headphone end? Give it a good waggle around the headset/each earpiece.
Is the headphone monitoring level (on the side of the camcorder body) turned up to a sufficient level?
Do the headphones have a volume control in their lead? (Turn it fully up, and tape over it.)
What have you selected via the audio monitor switch? Toggle the switch through its positions to eliminate the possibility of a faulty connection.
If none of the above produce results, plug in your spare set of headphones and repeat the process.
Sound signal chain
Assuming your headphones/monitoring are working correctly, switch back to the rear inputs, and work through your cabling and plugging – mic to camcorder – in sequence:
Are the cables fully plugged into your mic/s and the camcorder input/s? If in doubt, swap the leads over and/or check with a spare lead to eliminate cable faults. Waggle each cable end whilst monitoring for a signal.
Is phantom power turned on if it's necessary?
Plug up a different mic, especially a dynamic mic that doesn't need power.
Work back through the routing:
What is selected to channel one?
What is selected to channel two?
Check settings for front/mic/line and attenuation, if necessary. Switch backwards and forwards through the switch positions, the selector switch may be faulty/dirty. If you have plugged in a mic, check that mic/rear is selected for that channel.
For plugged mic channels, switch rec. level to manual, on both channels, and adjust gain/levels on the two circular dials labelled CH-1 and CH-2 whilst monitoring on headphones (the potentiometers may become ‘dirty’, especially if used in the same position with one mic for a long period of time and lose signal, turn them backwards and forwards several times to ‘clean’ them, and have them maintained as soon as possible). Is the channel one gain adjustment on the camera body turned fully up? The bar graph on the LCD display is a very rough guide, be confident on how it sounds on the headphones, if it sounds right, it is right. Sound at too high a level is also indicated by the limiter light, red LED, flashing (not DV).
If there is no signal, check to see that nothing looks broken, you'd remember if the equipment had been dropped/knocked between base and location, I'm sure. If there is a signal, but the camcorder won't record, check that the cassette is record enabled, i.e. that the red marker hasn't been accidentally pushed in/slid to one side. Moral: do not re-use cassettes.
Noise
There is a signal from your mic/s and the meters are working, but you can hear a noise/hum/buzz in your headphones, ‘Where's it coming from?’ you moan (usually loudly). First check your headphones by swapping them for your spare pair, is the noise still present, and at the same level/amount? Faulty headphones may produce a loading or mis-match on the monitoring circuit, producing a hum or buzz.
If the noise is still present, switch your monitor to channel one only. If the noise disappears then the problem may be on channel two. If the noise is still present, turn the channel one gain control up and down, does the noise level alter? If it does, then there is a problem with this channel (always assuming the problem simply isn't distortion caused by over-modulation, i.e. the gain turned up too high, but you'd see that on your meter, unless it was faulty). Alter the channel selection switch between on-camera mic and rear input (try it quickly several times to ensure it's not a faulty/dirty switch). If the noise is on both positions, it may be a monitoring fault. If it's only present on one position, then that is where the problem lies, change the mic or cable and/or turn the phantom power on and off.
If the noise persists after all your switching and re-plugging, it may be an internal wiring fault/dry joint/failing amplifier, or it may be a signal (RF) induced in the cable. Re-plug a spare mic on a short cable directly into channel one. If the noise disappears, then it is probably caused by induction on the mic/cable combination and/or routing and/or a cable fault. Make sure you do not run your sound cables close to mains power/cables. If the noise persists, you will have to avoid using the faulty mode, and feed sound with the switch selected to the non-noisy input.
If necessary, undertake the same procedure for channel two. Hopefully, you should have now managed to pinpoint the fault.
If, after undertaking all of the above checks, you can still hear noise, it may actually only be present on the monitoring circuit. Check this by inserting your test tape, and replaying a section of known quality. In all likelihood, if the noise persists. it is only the monitoring system at fault, but you should have the rushes checked as soon as possible on a player. If you can immediately send one off to an edit suite for a check, so much the better. If you have no test tape, then your only safe course of action is to find a way of replaying a tape on another player to ascertain if the fault is being recorded.
Intermittent noise
Intermittent noise may be caused by faulty wiring/cables/connections, or it may be induced from some form of RF transmission. Culprits are:
Mobile phones (ensure everyone on location turns theirs off! Switching to silent/vibrate is not sufficient, they MUST BE OFF).
Radio and/or TV transmitters in the vicinity.
Radar.
Magnetos (especially on board boats).
Large plant or machinery with electric power switching.
Electrically driven/operated vehicles, for example, fork lifts, milk floats, etc.
Need I say, radio mics are especially prone to these sources of interference (see also Section 9, Mics: cables and radio; Radio mic rules). You will need to move sufficiently far from the source of the interference in order to proceed, unless you can simply turn it off for the duration of your recording. Having said that, moving your receiver closer to the transmitter may also eliminate the problem, but if you do so, be aware that this may only prove to be a temporary fix. If the problem itself is due to a moving source, this could again come closer to your operating position and re-generate the fault.