Hi Harlan,
First let me say that these questions might be best asked on the yahoo groups UVB Meter Owners page. Secondly, the difference among MBV bulbs occur a continuum so providing discrete answers to your questions is not necessary possible.
I also want to stress that MVB bulbs are a bit of a nusance. Some decay or burn out relatively quickly and the companies return policies are not always as good as they indicate. Generally the people who are willing to put of with these tradeoffs are those keeping animals which really seem to benefit from intense amounts of UVA and UVB. Iguanas, Bearded Dragons, Uromastyx, etc.
With that said...
>>1. they give off both uva and uvb?
Yes, just about any UV producing reptile bulb gives off at least some of both. It's the intensity of specific wavelengths that varies.
>>2. how far does the uvb go?
Varies dramatically.
>>3.are all these products the same or is it a "you get what you pay for" type thing?
Not all the same and I believe some expensive bulbs are not very good.
>>4.these give off enough heat to be considered, say, a 100 watt basking bulb?
MVB bulbs come in both self-ballasted and externally ballasted types. It's the ballast that produces so much heat so the self-ballasted tend to get very hot. Hotter than an incandescent bulb of the same wattage.
>>5. are they all the screw in type, or are some tube type?
All standard screw in as far as I know.
>>6. how much uvb is given off? are there types for tropical herps and desert herps too?
ReptileUV.com makes MVB's for various types of herps. Again, the amount of UVR vareis quite a bit.
>>7. i imagine that like all uvb the type from these bulbs is stopped by glass fine mesh etc..?
I'd say greatly reduced. If you're going to put up with the nusances of MVB's you really need to take care to avoid transmitting through glass and use a larger mesh when possible.
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Current snakes:
0.2 Gonyosoma oxycephala - (Silver/Yellow)
3.3 Gonyosoma oxycephala - (Green)
2.1 Gonyosoma janseni - (Black)
3.3 Gonyosoma janseni - (Black & Tan)
