Dear Wallace: Thank you for your input and giving me the opportunity to provide Dampp-Chaser's point of view. First, we can do anything (well almost anything). We can build whatever product technicians want. I believe we usually do. The vast majority of our new product ideas come from technicians. Yes we can build a humidistat that has a "dead band" built into its circuitry. As a matter of fact we have built several. By "dead band" I mean an area within the relative humidity scale where nothing happens. Neither the humidifier nor the dehumidifier are on. We go through the design and cost engineering of this type of unit every year or so to see what has changed since the previous look, both from a component development point of view and a cost stand point. Each evaluation to date has yielded a humidistat cost of more than twice that of our current unit. The costs are coming down however. By way of background, our electronics engineer is Keith Howell, one of the top design and engineering minds in the country. Keith is retired from GE and is one of a team of 3 engineers responsible for developing the Triac. The above implies that our quest is to provide "dead band". Nothing could be further from the truth. "Dead band" is a by product. It may be desirable, but if it is, it is only marginally so. Actually what we are looking for is a switch with a reduced differential. This would be a plus in our humidor and printer case systems (at least a perceived benefit). I'm not sure that it would be of any great benefit in the piano application, but if we could do it for essentially no additional cost (or very small additional cost) we would. At any rate, most technicians and their customers don't want to pay any more for the product than they are right now. As a result, we watch our costs very closely and do everything we can to reduce them. We try very hard not to increase prices. Now, herein lies the problem. In order for us to significantly change the product and correspondingly, the cost of the product, there has to be general acceptance by consuming technicians that the improvement warrants the price increase. I honestly don't get that response to this situation. I'm all ears however. If a significant number of you folks say you think creating a "dead band" or small differential is worth a 30% increase in the cost of the system, we sure will consider it further. Let me add a further consideration, and that is the sensor used is similar to that used in the small electronic hygrometers. I'm told that over a period of time a film develops on the sensor face, and it becomes inaccurate. By comparison we get H1 humidistats back for testing that are as accurate now as the day they were manufactured. We stopped manufacturing the H1 ten years ago. I know I've gone further in this discussion than the timer you suggested. It seemed to me though that if we were going to add the cost of a timer we might as well go to the electronic unit to produce a dead band and smaller differential; i.e. do the job completely. It's also possible that this creation would not be anymore expensive than the timer addition. Everything considered it might even be less expensive. On the face of it, there is nothing I'd like more than to provide the piano owner knowledge of when the humidifier is on, and when the dehumidifier is on. With all due respect though, I don't want to answer all the phone calls we will get that go, "it's raining outside, and the humidifier in my piano is on. It shouldn't be on". You would be surprised at how many phone calls I get now that ask essentially this question. I don't mind answering, but it does take time. Actually, from my experience, technicians and piano owners are interested in the result; is the piano stable, rather than how it got there or what the humidity control system is doing. Certainly this is true after the novelty of system wears off. Frank Leister used the phrase, "it seems like the system is fighting itself." Many systems in our everyday world cycle. Some because they are driven in both directions; some because they are driven in one direction and are allowed drift back in the other direction. The Dampp-Chaser system happens to be driven in both directions. I don't think that's particularly unusual. To me the system would be fighting itself if both the humidifier and dehumidifier were on at the same time. Then it would be a contest to see which part of the system wins. In summary, I've made the following points: 1) Cycling isn't unusual. It's o.k. It's not really fighting. 2) We look at creating a humidistat with reduced differential (and therefore dead band) every so often and continue to come to the conclusion it's not worth the expense. Further, there is question as to its acceptance based on price by technicians. There is also the question of its long term reliability. 3) The addition of light signals to describe what is happening within the piano is neat for technically oriented people, but is it worth it for most technicians and piano owners? You have my thanks for responding to my post to Frank Leister. It takes all kinds of feedback to get a complete picture. Please continue to write in the future. Sincerely, Bob Mair cc: Mike Mohr Ken Eschete Frank Leister
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