Goodmans 336 NS

Wow, old school! Humm...If I remember High gain input will distort a wave form. This means the amp increases the wave voltage to pass the maximum available voltage. But since it can't go any higher in voltage, the wave stops at the max (what ever the supply high voltage is rated at) then flattens out at this peak level until the wave drops back down. Your signal distorts any time the feed goes over the limit. Sometimes this is done on purpose as in Guitar amps where there is a separate dial that controls this 'effect'. I'm guessing you are using a regular amp with very simple controls like volume, tone (Bass, Trebble). Some older dedicated amps do not have a volume input but may have a 'Gain' knob which just about serves the same purpose as the volume control. This gain knob is usually set at a level BEFORE distortion can set in from your signal source. Hopefully once properly set you won't overdrive the amp and get unwanted distortion. The problem rises when there are multiple sources of signal say from a Radio Tuner, Turntable (ceramic or Magnetic), and the newer CD, DVD, MP3 players. You must also note that many of the devices after Y2K (wow 18 years ago!) don't have a 'Line' or low level output. Most equip only have earphone outputs which will be too high for use on amplifier. High level output are used to drive head phones or ear buds. You must use anttenuator device to reduce the power for low level use. Donno, if those are still around as Radio Shack stores have closed down.
* Okay assuming you know all this and your amp WAS working normally at one time, AND this is an old 1950-1970's tube amp. Then you probably have a shorted (burnt?) gain or volume knob. Volume Resistor (Pot) cleaner sprayed into component may help. But usually components this old will need replacement. Dirty pots will cause cracks, pops, and scratchy sounds from speaker. This is the most common cause for unstable volume (gain) in amps.
* Another problem may be a shorted or partially bad signal capacitor which is just off the volume/gain pot or directly at the input of the amp section. Capacitors may go bad if a voltage spike (surge) hits it. These are low voltage devices so it does not take much to spike them. Electrolitic caps will sometimes self heal but fail again as input voltages spike near it's limit. You will need an audio electronic tech to go through and check all the components and replace as needed. Yes this is costly as there are not many 'old school' people around. But with some of these antique prices for tube amplifiers (especially bass guitar amps) you have to decide if it's worth it. There are new tube amps out there for audio pureists, so you may want to check that option.
* Okay, worst for last. Tube going bad (very common). Good luck on finding a replacement. I've seen them available on eBay and Amazon but don't know the quality. Very old TV/Radio shops in an old town may have them and worth a check if they are still open. You may also find them at an old music store.
* There are other possible problems (Power supply, Transformer, Bad contacts on tube socket, Bad solder joints, etc.) But really require a tech to trouble shoot and locating replacement parts to initiate repairs.
* since the problem shows up after the amp is heated up and hot. Check the vents for dust and vac out cob webs and debris. Placing a small (small!) fan to blow on the back may help, but over heating usually causes the power supply to heat up as well and may cause arcs in the high voltage section. High heat also breaks down old style capacitors.
* There is a reason why most people switched to transistors and now power ICs. Tubes have a warmer tone that few people can detect as most of us (Rockin '60-70's) have blown out our hearing long ago.
Aloha, ukeboy57

A spike is an increase in voltage for 1-2 nanoseconds.
A surge is the increase lasts 3+ nanoseconds.

You most likely have an improper ground or no ground at all. Ground out your amp and the will probably take care of the noise. The other thing that can cause this is cross over from a high voltage source. You may have your low voltage lines to close to high voltage and getting bleeding of signal. The last thing, which should really be the first thing to check, is connections. One strand of copper not conntected can cause all sorts of problems.

Your issue is that the dimmer is not rated to handle the type of fixture/lamps its controlling.

From a lighting control standpoint, the 12V-lamps classify as "low-voltage halogen" and, somewhere in that circuit, have a transformer(s) converting the 120V~ down to 12V~. Using incandescent dimmers (like the one you are using) can cause compatibility issues with those transformers. What I suspect is happening is that the incompatibily is either throwing voltage spikes or current spikes on the line which are causing the dimmer to enter some sort of "safety" mode to shut everything down before any problems occur.

My recommendation is to first figure out what type of transformer it is: Either magnetic low-voltage, or electronic low-voltage. Ideally you would contact the transformer manufacturer (or look up their specs online) to figure that out. Other rules of thumb: if the transformer's big & bulky, it's probably magnetic - conversely if its lightweight, it's probably electronic. If its only one transformer controlling all of the lamps together, it's probably magnetic - conversely if its one of those transformers where the transformer and light bulb come togheter as one assembled unit and then snap into the track, it's probably electronic.

Then make sure the dimmer is rated for magnetic low-voltage, or electronic low-voltage (depending upon what the transformer is).

Make sure the thermostat is calling for the respective seaon and see if it works. A power outage shouldnt interrupt the furnace unless you had really low voltage or a voltage spike. Try it and see

White wires are commonly the common connection (sorry for the pun). L2 is also considered the common leg. You did not mention if you are looking for high voltage or low voltage common. L2 is your high voltage leg. If the power venter ties into the thermostat circuit, W on the circuit board is the common terminal.

If voltage is present, it has to be the bulb, usually, depending on the socket. Look at the socket closely, and make sure that the base makes proper contact with the bulb. They can distort just enough to trick you. If you can, make a set of mini-jumpers with alligator clips and wire. Connect from the base (socket) to a known good bulb. It's quite possible that there can be voltage present in the wiring, and none to the light, indicating that either there is a problem with the connection where the wiring passes through on the way to the next light, or in the fixture itself. My guess is that in the press-on connection, one of the spikes has missed the wire. Take that apart and reconnect; it'll probably do the trick.
Regards, --W/D--

I would think that:

Low voltage. A lack of proper voltage increases the current flow (amps) and can cause overheating, thus, a burnt wire. Remember, the lower the voltage, the higher the amps.

Bad connection. Poor connections can cause small amounts of arcing, thus burning the connection. This adds resistance to the circuit which causes a possible voltage drop and, again overheating due to higher amps.

Since all that equipment is on the same circuit, I would really think it is a voltage drop situation. With everything calling for power at the same time, the breaker trips. In some cases, it may be just enough for the breaker not to trip but still have a low voltage situation.

There is the possibility of an over current, such as a power spike from the power company but it would have to happen more than just a time or two.
And the outside chance that lighting got into the system when it struck something close to you home but it, in almost every case, would destroy something else, usually electronic. (This has happened to me. Trashed my dryer, dishwasher, and answering machine.)

Good luck and hope this helps. Le me know how you come out.

In this case is pretty hard to give a diagnostic. There are plenty of possibilities. It has to be seen by a tech