3 engine rooms in the TOS Enterprise's engineering hull?

[Robert Comsol]

I am aware that the essential subject has already been discussed but after a variety of recent observations for my TOS Enterprise WIP and a suggestion of a friend I won't exclude the possibility that we might be looking at a minimum of a) three engine rooms in the b) "engineering section" of the c) engineering hull.

In TOS there is a variety of episodes that are outspoken clear about the warp engines or nacelles containing antimatter and matter-antimatter reactors and blssdwlf has not only compiled these canonical dialogue statements but also drawn some fascinating conclusions (three matter-antimatter reactors) he posted and illustrated in his thread: http://www.trekbbs.com/showthread.php?t=119751&page=16
(I recommend starting at post # 229).

I believe the dilithium re-amplifying room from The Alternative Factor to be separate place where you take exhausted crystals from the dilithium crystal ‘cage’ in the middle of the double-triangle casing in the (warp) engine room for “re-amplification”. To power the warp drive (and else) they have to be placed back in their cage(s) for performance.



As it appears the cage can only hold one crystal at a time and I presume the matter-antimatter annihilation energy from the nacelles’ reactors (in addition to the TOS “warp core” suggested by That Which Survives) is also routed through two crystals easily accessible for replacement by the engineering personnel and located somewhere in the engineering hull.

The very TOS beginning and Mudd’s Women suggested that all three matter-antimatter reactors of the Enterprise were working at full power chasing Mudd’s ship through an asteroid field resulting in the subsequent burnout of (di)lithium circuits and subsequent shutdowns of the reactors:

CREWMAN [OC]: This is the Engine room. Temperatures are passing the danger line.
FARRELL Our deflector screen's weakening, sir. We can't protect them much longer. (lights flicker)
SULU: That was one of our lithium crystal circuits, sir.
KIRK: Bridge to transporter room. If you don't start beaming that crew over soon
SCOTT [OC]: They're not answering our signal. There's nothing to lock onto.
SULU (lights go out again) Another circuit, sir.
...
SULU: Another lithium circuit. Now supplementing with battery power, sir.

At this time they appear to have only had three dilithium crystals circuits onboard (and no shuttlecraft ).
If the structure in the engineering section only holds one dilithium crystal circuit, where is the location of the other two as it is unlikely they exchanged dilithium crystal circuits during the chase (!)?

My friend wondered if the shaking and G-Force pressure seen in The Doomsday Machine might be an indicator of engine room orientation aboard the Constellation but I attributed the erratic movement of Scotty to hickups of the damaged inertial dampers and/or unfamiliarity of the director with the Enterprise’s deck layout, which IMHO could look like this: https://www.dropbox.com/s/yscj4a4hid0p2v7/USS%20Enterprise%20Engineering%20Deck%209%20Uncompressed.jpg

However, with The Immunity Syndrome I feel that’s a more complicated story. We had already seen in an earlier episode produced (Mirror, Mirror) a rectangular console in the Emergency Manual Monitor (EMM) on the upper level of the (warp) engine room, yet for The Immunity Syndrome they decided a) to remove the rectangular console and b) to put the semi-circular console from the Auxilary Control Room in its place instead - to suggest this is a different engine room?!



In the scene from this episode, when they combine warp and impulse power for one major forward thrust, we see accordingly on the bridge that they are all being pressed into their seats and towards the stern of the ship.



However, in the engine room that’s a totally different story. To the left side of 'this' engine room would be the entry and to the right side the ‘cathedral’ with its tubes (studio set).
Thus the shot of the warp engine room seen from this “EMM” clearly suggests that the bow of the ship is to the right and the stern is to the left which would make this another engine room with a dilithium crystal cage as it apparently can’t be the (main) warp engine room in the center of the engineering hull.



Now, do we have to consider the existence of one starboard warp engine room, one to the port and one in the center? I doubt there'd be enough space.

Bob

 

[Albertese]

I haven't really started on the engineering hull on my deck plans project, but I'm of the opinion that there are numerous compartments that look like the "engine room" sprinkled liberally throughout the hull. Three such rooms would be my minimum. But they don't necessarily have to side by side.

I've already managed to fit one such room in the saucer near the impulse engines. And I've even made it five feet longer then the real set and it fits beautifully. Of course, I'm using a 1080' Enterprise rather than 947'. Also I'm using the exterior proportions of the AMT model kit rather than the 11' studio miniature.

--Alex

 

[Mytran]

Three engine rooms needn't be on the same level: Perhaps two side by side on Deck 14, and a third located on another deck above?

The biggest problem is that it will start to impact on your (Robert_Comsol's) delicate corridor structure.

 

[blssdwlf]

Alternatively, what if there were four engine rooms? There were 4 lithium circuits that were blown in "Mudd's Women" and the ship in "The Alternative Factor" required 4 dilithium crystals to operate at full power.

One of the reasons that I chose to have all four crystals in one place (or one room) was because there was only one crystal converter assembly in both "Mudd's Women" and "Elaan of Troyius" suggesting a single point of failure rather than 4 different points that can fail.

Also, not all Season 2/3 engine rooms had the slide-up crystal holder. I think there was one episode that had some other rectangular device there instead. So you might need to have enough engine rooms for each crystal PLUS one more that doesn't have it. Am I correct to assume that in the engine room per crystal scenario that the Season 1 engine rooms are still also on the ship?

 

[Robert Comsol]

"Alternatively, what if there were four engine rooms? There were 4 lithium circuits that were blown in "Mudd's Women" and the ship in "The Alternative Factor" required 4 dilithium crystals to operate at full power."

According to the above quote from "Mudd's Women" there seem to have only been three and Scotty suggests that, too:

[Transporter room]
SPOCK: What's wrong?
SCOTT: I don't know, sir. With those three lithium crystals gone
SPOCK: It'll take longer on battery power.
MCCOY: Never trusted this.

"One of the reasons that I chose to have all four crystals in one place (or one room) was because there was only one crystal converter assembly in both "Mudd's Women" and "Elaan of Troyius" suggesting a single point of failure rather than 4 different points that can fail."

There was only one crystal converter assembly in "Mudd's Women"? Indeed, "Elaan of Troyius" suggested one "dilithium crystal converter assembly" (and I'm still wondering how they defused the "bomb" only to find out after that that the entire assembly had been "fused" ).

"Also, not all Season 2/3 engine rooms had the slide-up crystal holder. I think there was one episode that had some other rectangular device there instead. So you might need to have enough engine rooms for each crystal PLUS one more that doesn't have it. Am I correct to assume that in the engine room per crystal scenario that the Season 1 engine rooms are still also on the ship?"

You're right, it appears the rectangular box was there throughout the second season starting in "The Doomsday Machine"



and in "The Changeling"



and in "Journey to Babel"



and in "The Immunity Syndrome" (lower right side)



and in "The Ultimate Computer"



It appears that the central engine room in the engineering hull doesn't have it or didn't prior to Season Three.

We might, of course, be looking at a practical upgrade: Originally, you had to take the matter-antimatter reactors offline to remove and replace dilithium crytals, maybe through that hatch or drawer below Scotty's communicator:



Maybe the upgrade enabled the removal and replacement of one dilithium circuit at a time while the reactors are working. Scotty suggested to do that in "The Paradise Syndrome" but Spock felt the replacement procedure to be too time consuming. In "Elaan of Troyius" they were merely able to replace one circuit with the raw dilithium crystals but obviously enough to give them warp power (they used photon torpedos to disable the Klingon Battlecruiser).

I assume the Season One "Engineering Control Room" to still be on the saucer's port side and wonder if the one from "The Immunity Syndrome" might possibly be the one on the saucer's starboard side (I usually associate the grey housing on the engine room's floor with warp drive functions but the console from the Auxilary Control Room does a great job hiding it from sight...).

After all, the idea was to combine warp and impulse propulsion into one major forward thrust. I'd like to believe this required a manual override (i.e. to add impulse power) and that this was what Scotty had been doing in "The Immunity Syndrome".

Bob

 

[Timo]

it appears the cage can only hold one crystal at a time

It might be more like a single terminal for a "micro-turbolift" system that delivers the crystals deep into the bowels of the lethally radiating reactor machinery - but with multiple "turbolifts" to receive and deliver the crystals, either to their points of application, or then to waiting positions.

The little "lifts" could then accept either macroscopic natural crystals in those holding frames, or arrays of microscopic (synthetic?) crystals in the ping-pong paddle frames seen in "Alternative Factor".

This would lift most restrictions on engine room relative geometry, as the "turboshafts" could zigzag anywhere. The pedestal Spock manipulates in ST2:TWoK to bring main energizers back on line would be the more modern equivalent of this dumbwaiter system, similarly delivering to some underfloor reaction focus... If need be, to the one seen in ST6:TUC and featuring a TNG-style dilithium chamber!

Timo Saloniemi

 

[Mytran]

"Alternatively, what if there were four engine rooms? There were 4 lithium circuits that were blown in "Mudd's Women" and the ship in "The Alternative Factor" required 4 dilithium crystals to operate at full power."

According to the above quote from "Mudd's Women" there seem to have only been three and Scotty suggests that, too:

[Transporter room]
SPOCK: What's wrong?
SCOTT: I don't know, sir. With those three lithium crystals gone
SPOCK: It'll take longer on battery power.
MCCOY: Never trusted this.

Although three crystal circuits blew, there was a fourth crystal still intact, albeit cracked. From later in the show:

SCOTT: We've got trouble, Mister Spock.
SPOCK: I'm well aware of that, Mister Scott.
SCOTT: One lithium crystal left, and that with a hairline split at the base.
SPOCK: Better rig a by-pass circuit.
SCOTT: Can't. We blew the whole converter assembly.

and...

SPOCK: The entire ship's power is feeding through one lithium crystal.
KIRK: Well, switch to by-pass circuits.
SCOTT: We burned them all out when we super-heated. That jackass Walsh not only wrecked his vessel, but in saving his skin
KIRK: If it makes you feel better, Engineer, that's one jackass we're going to see skinned.
SCOTT: But it's frustrating. Almost a million gross tons of vessel depending on a hunk of crystal the size of my fist.
SPOCK: And that crystal won't hold up, not pulling all our power through it.

 

[Robert Comsol]

it appears the cage can only hold one crystal at a time

It might be more like a single terminal for a "micro-turbolift" system that delivers the crystals deep into the bowels of the lethally radiating reactor machinery - but with multiple "turbolifts" to receive and deliver the crystals, either to their points of application, or then to waiting positions.

The little "lifts" could then accept either macroscopic natural crystals in those holding frames, or arrays of microscopic (synthetic?) crystals in the ping-pong paddle frames seen in "Alternative Factor".

Great thought, problem solved.

Bob

@ Mytran

Thanks for the correction, I overlooked this piece of dialogue. So they kept one dilithium crystal in storage for emergencies but didn't check its condition before they put it there?

 

[Mytran]

Honestly, I think the dialogue is suggesting that the trauma which blew the other crystals put a crack in the 4th one (suggesting 4 crystal assemblies). But your explanation is also quite valid - maybe that's why it is the spare crystal?!

The Alternative Factor features 4 Dilithium "paddles" which (to my mind) echo the 4 crystals in Mudd's Women.

Finally, Kirk negotiates for 6 crystals with the miners. Either the Enterprise has the capacity to run on 6 crystals, or he was thinking ahead to the next incident, and wanted spares!

 

[Robert Comsol]

"Honestly, I think the dialogue is suggesting that the trauma which blew the other crystals put a crack in the 4th one (suggesting 4 crystal assemblies). But your explanation is also quite valid - maybe that's why it is the spare crystal?!"

I think it literally is a spare. According to "Elaan of Troyius" they needed at least one dilithium circuit (substitute) to have warp drive capability. Looks like that's the minimum to be capable to get to the nearest service station for a replenishment.

"The Alternative Factor features 4 Dilithium "paddles" which (to my mind) echo the 4 crystals in Mudd's Women.

Finally, Kirk negotiates for 6 crystals with the miners. Either the Enterprise has the capacity to run on 6 crystals, or he was thinking ahead to the next incident, and wanted spares!"

Makes perfect sense to me. The Re-Amplification Chamber seems to have space for 12 "paddles" (the 6 drawers seem to match the 6 rows of indicators on the control panel's right side) of which four seem to be able to be re-amplified (4 small and 4 big control knobs) or tested ("experimentation chamber"?).

Since the episode suggests these "paddles" are in widespread use in the known galaxy (they are perfectly compatible with Lazarus' craft) the Enterprise may also have the capacity to re-amplify dilithium circuits of other ships that require assistance but don't have onboard re-amplifying facilities.

Of course, we can't exclude the possibility that Kirk wanted 6 crystals because he knew that the cutting process to bring these crystals into the universal paddle shape usually results in the loss of 1 out of 2 crystals.

Bob

 

[Timo]

The interesting issue about "Mudd's Women" is whether just one or several crystals are in active use at a given time. We don't see the heroes suffer from a visible "hiccup" of power when each of the crystals blows, but OTOH we don't see them suffer from a stepwise loss of power, either. So it could be that just one crystal at a time is "running", and when it blows, another comes on line very quickly (it's on a "circuit" of its own, waiting, and a simple flick of a switch selects a fresh circuit as needed), and the power is kept steady; using multiple crystals doesn't give more power, and may not even be possible in the first place. When a single crystal fails to give "full" power, this may be attributed to the cracks in it, rather than to the lack of multiple parallel crystals.

Compare to "Alternative Factor", then. The universal hiccup drains "almost all" of the crystals. We don't learn whether these would have been hooked up to machinery or waiting in storage, or perhaps being "active spares" already dumbwaitered into the machinery but still waiting for their turn to serve at the m/am reaction focus. Kirk needs "full" crystal power, but does not explicate whether this calls for multiple crystals, or merely for a single non-drained one; naturally, he would order all crystals "re-amplified" immediately in both scenarios.

Yet when the first Lazarus steals two crystals, Kirk exclaims that with them missing, the ship cannot operate at full power. Of course, even with the theft of two more and the apparent loss of the energizer room, the ship still retains the ability to orbit, to beam people up and down, and to fire weapons... But it does appear as if a fairly large number of (paddle-type) crystals are needed simultaneously to yield "full power". Not so many that two would represent an insignificant fraction - but not so few that loss of two or even four would completely deprive the ship of power.

Since just three were lost in "Mudd's Women", and the ship still struggled, we're probably speaking of a fairly fuzzy system here. Just one will give warp in a cinch; something like six may be on line simultaneously for maximum power and flexibility; and Kirk can live with having four available, for single or simultaneous running, but will be quite worried when facing a crisis with a minimum of (still partially drained?) two.

Perhaps the parallel use of crystals for "full power" doesn't mean they are all active? Perhaps it just means that Scotty will not have the courage to throw the lever on the single active crystal to "full" unless he has at least three fully amplified backup crystals available in the reactor system?

Timo Saloniemi

 

[blssdwlf]

In "Mudd's Women", after the 3rd circuit blew out, they had to use battery power for the transport of the 3 women. During that time, they still had to maintain maneuvering and shields to protect Mudd's ship which in mind, lead to the cracking of the 4th crystal.

The problem with the 4th crystal being a spare is why does it have a crack in it since it would've been put in operation after the ship was no longer under stress?

 

[Robert Comsol]

"Yet when the first Lazarus steals two crystals, Kirk exclaims that with them missing, the ship cannot operate at full power. Of course, even with the theft of two more and the apparent loss of the energizer room, the ship still retains the ability to orbit, to beam people up and down, and to fire weapons... But it does appear as if a fairly large number of (paddle-type) crystals are needed simultaneously to yield "full power". Not so many that two would represent an insignificant fraction - but not so few that loss of two or even four would completely deprive the ship of power."

Interesting theory, but let's take a look at "Mudd's Women" again. They burn out 3 dilithium circuits and immediately have to switch to battery power. Then, they discover they have a spare but flawed one they can somehow make work. In the meantime the entire ship relied on "battery power" and was still capable to beam over the three Women.

The events in "The Alternative Factor" could be much alike. The ship is on "battery power" and will allow Kirk and security personnel to beam down and back up. They recover the two dilithium circuits, put these back and thus have a) warp and b) phaser capability to destroy Lazarus' craft.

I just took a second look at "The Paradise Syndrome". While Scotty was concerned about the deterioration of the dilithium circuits, his major concern were the warp engines:

SCOTT [OC]: We'll burn out the engines!
SPOCK: I want full power, Mister Scott.
...
SCOTT [OC]: Don't ask for anymore warp nine speeds, Mister Spock. Our star drive is completely burned out. The only thing we have left is impulse power.

It appears they were stuck with impulse power not because the dilithium circuits failed but because of physical damage to the warp nacelles.

Bob

 

[Timo]

...Or perhaps the fourth crystal was already cracked, which is why it wasn't in use at all, but was put to use when there we no intact crystals left?

"Mudd's Women" does seem to establish that battery power was needed to supplement other remaining sources of power after three crystals were lost, and still gave reduced performance. So the loss of the three crystals

a) didn't result in the loss of all power other than battery power (because it's "supplement" rather than "supplant")
b) reduced performance

which may mean that loss of a crystal results in a drop in power and loss of three results in three cumulative drops but only a loss of a fourth would drop power to zero. But it may also mean that a single crystal is working at any given time, giving full power, and the battery power had to be added because the fourth crystal to take on the job was inferior to the first three (that is, it had a crack in it).

Later we hear Spock say that all the ship's power is running through a single crystal. Supposedly, then, this is unusual. But Kirk is not worried: his suggested remedy is using bypass circuits, which Spock then says were burned during the chase. Remember that when the three crystal circuits blew, Kirk was on the bridge, and we never heard anybody in the transporter room tell him about the crystal circuits blowing. Spock only heard of all of them being gone because he was present at the transporter room. Sulu on the bridge commented on "another" being lost, meaning the bridge team necessarily knew of at least two losses, but possibly only knew of two losses rather than of the alarming situation where there only was one crystal left.

Again possibly a reason to think that loss of a crystal has no observable effect if a spare can be brought on line, and Kirk never noticed anything seriously amiss because spares did come on line, one by one?

EDIT: oops, you beat me to it, Bob! But see the different nuances in the rationalizations, with a "pre-cracked inferior spare online with batteries" vs. "battery power until inferior pre-cracked spare can be brought online".

Timo Saloniemi

 

[Robert Comsol]

"In "Mudd's Women", after the 3rd circuit blew out, they had to use battery power for the transport of the 3 women. During that time, they still had to maintain maneuvering and shields to protect Mudd's ship which in mind, lead to the cracking of the 4th crystal."

Or the shields were equally powered by this enigmatic "battery power":

FARRELL: We're clearing the asteroid belt now, Captain.
KIRK: Deflector screen down, Mister Farrell. Save the power.

We do know from "Mudd's Women" that the Enterprise only had 4 dilithium circuits onboard, we have seen 4 dilithium circuits in "The Alternative Factor" and do not know the exact energy output of "battery power".

Bob

 

[Robert Comsol]

"But see the different nuances in the rationalizations, with a "pre-cracked inferior spare online with batteries" vs. "battery power until inferior pre-cracked spare can be brought online"."

Yes, and I definitely rather prefer to believe they were aware they (still) had a pre-cracked one they could use than to assume the spare was already damaged when brought aboard.

Bob

 

[Timo]

Ah, I meant "already cracked" when saying "pre-cracked", that is, I think Scotty knew fully well that he had a range of crystals aboard, from pristine to really substandard. It's just that this is the best Starfleet could provide him with, (di)lithium being such a rare resource. So he brought them on line one by one, finally keying in the cracked crystal he had been stashing away for a really rainy day.

Timo Saloniemi

 

[blssdwlf]

"In "Mudd's Women", after the 3rd circuit blew out, they had to use battery power for the transport of the 3 women. During that time, they still had to maintain maneuvering and shields to protect Mudd's ship which in mind, lead to the cracking of the 4th crystal."

Or the shields were equally powered by this enigmatic "battery power":

FARRELL: We're clearing the asteroid belt now, Captain.
KIRK: Deflector screen down, Mister Farrell. Save the power.

Since Kirk was aware of the circuits burning out he could've just as well been referring to saving the 4th and last circuit from going out.

We do know from "Mudd's Women" that the Enterprise only had 4 dilithium circuits onboard, we have seen 4 dilithium circuits in "The Alternative Factor" and do not know the exact energy output of "battery power".

We also know that the battery power was brought on to make up for the loss of the 3 circuits, not that it was substituting for ALL power (the difference between "supplement" and "supplant").

SULU: Another lithium circuit. Now supplementing with battery power, sir.
​

Because it was supplementing the power system, it is far more likely that there was a fourth active circuit that was powering the warp engines and the shields that were projected forward onto Mudd's ship. This would explain why the crystal was cracked and not a pristine one that was brought out of storage.

In "The Alternative Factor" they lost all four crystals but unlike "Mudd's Women" and "Elaan of Troyius", they have a working crystal converter assembly and thus they can still activate the bypass. In this case, they were likely not on battery power at all.


So to recap, basically we have a few different theories:

• There are 3 active dilithium crystal circuits with a corresponding engine room. The 4th dilithium crystal circuit is a spare circuit. Does it have it's own engine room? When all 3 circuits go out, someone has to manually bring online the 4th one? Or install it?
• There are 3 active dilithium crystal circuits with a 4th "hot" standby circuit. I don't know if Timo is advocating separate engine rooms.
• There are 4 lithium/dilithium crystal circuits housed in a single crystal converter assembly. In Season 1, it was in the Main Energizer room. In Season 2 and later it was moved under one of the engine rooms in the engineering hull.

EDIT:


On the ones with separate engine rooms per crystal, how does a single crystal converter assembly work in the system?

 

[Albertese]

The crystals referenced in "Mudd's Women" are not the paddle crystals seen later. Spock has one in the briefing room and it is a fist-sized (as per Scotty's lament about all the power channeling through a single crystal the size of his fist) clear faceted large diamond-esque crystal-ly looking crystal.

I posit that there are four of these crystals (which are not at all un-like the dilithium crystals as seen in TNG) that are used in anti-matter reactors to provide main power.

I suggest the paddles are a manufactured product. When raw, natural dilithium is faceted to work in the reactor, the ground off material is pressed into a standardized paddle form. The natural cut crystals can't be re-energized (as per Star Trek IV) but the smaller paddle crystals can be re-energized. Perhaps through use, the artificial crystalline structure is disrupted but these can be put into a re-energizing device which re-aligns the structure.

I further suggest that these paddles are used as batteries, and the battery power is in fact banks of these paddles. The times we see them being used in conjunction with the structure in the season 2-3 Engineering set could suggest that they are used (like the battery in a car) to jump start the system.

Makes sense to me...

--Alex

 

[Robert Comsol]

@ Albertese

Looks like we got carried away, thanks.

Spock presents the last crystal to Kirk in his cabin just prior to the arrival of the miners and it looks like a crystal and not like the 'paddle'. Maybe the change in appearance is another changed premise in the series or they used lithium crystals prior to dilithium crystals / paddles (maybe the "di" prefix stands for the mounting compatible ends ?) or else. But after the last / fourth crystal burned out, do I hear Kirk saying "the lithium crystals" or "dilithium crystals"?

I have a few concerns about re-interpreting actual dialogue.
In "The Alternative Factor" Kirk orders Masters to immediately "re-amplify" the dilithium paddles and they later talk about "re-amplification" which I believe is more in line with the re-crystalisation mentioned in ST IV than simply charging these with energy like batteries. There is no evidence that the crystals are being "re-energised" only that the "energiser" providing energy for the re-amplification components is short circuited by Lazarus.

The other thing is that the cage (or structure it sits in) in the engine room is a "dilithium crystal converter assembly". Another component specifically mentioned in TOS are "power converters". As to what these dilithium crystals convert may be a subject of speculation if one doesn't want to follow the official line but conversion seems the major purpose of dilithium crystals.

@ blssdwlf

# 1 - There are 3 active dilithium crystal circuits with a corresponding engine room for each of the three crystals (should the crystal in one of the engine rooms fail, the "cycling station" will reroute power from the remaining two to compensate the power loss) The 4th dilithium crystal circuit is a spare circuit.

# 2 -There are 3 active dilithium crystal circuits with a 4th "hot" standby circuit in the warp engine room (1 for each of the three reactors).

# 3 - There are 4 lithium/dilithium crystal circuits housed in a single crystal converter assembly.

Does this cover all the options?

Where I'm unable to subscribe is "In Season 1, it was in the Main Energizer room."
The Re-Amplification room or chamber seemed to be a place for the dilithium paddles to rest and relax, not to work. If we were to assume that the paddles can rest and work at the same spot, the large GNDN pods in the engine rooms would seem to be more suitable candidates, IMHO.

Bob

P.S. What could "re-amplification" mean? Here's a quote from Wikipedia concerning "stability and aging" of "crystal oscillator" to illustrate the stress crystals could be exposed to:

"The frequency stability is determined by the crystal's Q. It is inversely dependent on the frequency, and on the constant that is dependent on the particular cut. Other factors influencing Q are the overtone used, the temperature, the level of driving of the crystal, the quality of the surface finish, the mechanical stresses imposed on the crystal by bonding and mounting, the geometry of the crystal and the attached electrodes, the material purity and defects in the crystal, type and pressure of the gas in the enclosure, interfering modes, and presence and absorbed dose of ionizing and neutron radiation."