1148 
MONITORING 
A redesigned transducer connector, easier to 
sterilize, should also be designed. 
DISCUSSION 
Chairman Franklin: Thank you, Eph. 
Since you've implicated me in some of these 
data, I really must ask a question if I may. Let 
us pose a situation where I buy ten of your 
pressure gauges, ten of the P22's. I'm not con- 
cerned about the two that are almost perfect 
nor am I concerned about the six that are pretty 
darn good. How about those two that you put 
down on the bottom end? What kind of zero 
drift can I expect in the first two months from 
those two? 
Dr. Konigsberg: Now you know the answer 
to that because I saw it in your papers. You can 
get as high as 30 per cent drift per month, but 
that was one bad actor. I think between 20 per 
cent and 25 per cent drift would take care of 
the rotten two out of ten gauges. 
Chairman: Well, I'd put a number some 
place in the middle there, but we're close to the 
same number in any event. Are there other ques- 
tions for Dr. Konigsberg? 
Dr. Konigsberg: Oh, can I answer that just 
one more time? Just a second. I would say that 
we're looking at the prediction of this. One of 
the troubles that we've had (and I meant to say 
it, but I thought of it after I wrote the paper) 
was that we measured one batch of transducers 
and Dean Franklin measured another batch of 
transducers. It would be really meaningful to 
measure for a reasonably short period of time 
a batch of transducers and then take that same 
batch and then evaluate it in vivo because that 
is what he would like to see. He would be happy 
and most people would be happy to pay a pre- 
mium and let us test them in our lab. Then take 
those bad 20 percenters, ship them to some place 
that doesn't know very much, or do something 
with them. Use them for chronic experiments 
at 50 per cent of list price and say it's only 
good for chronic. But the question is — can we 
correlate good versus bad in the laboratory, 
versus in vivo. I believe we can, and I think this 
is the next step, to buy a pre-selected trans- 
ducer. Don't buy anything unless it's been in 
a cycling pressure system for a month, and this 
is being done now by NASA. We have a batch of 
ten or twelve transducers on life test. They're 
going to be measured every month and the ones 
that are going to be put in their biotelemetry 
systems will be the best ones. The worst ones, 
we'll keep looking at and they will either stabi- 
lize or we'll junk them. I think this is the 
approach. 
We will know this in a year, because first we 
test them w vitro and then in vivo. 
Chairman: But I'm not interested in what 
will happen in a year because I am buying ten 
pressure gauges and so on. 
P. Somani, Abbott Laboratories, North Chi- 
cago : This seems very interesting for those who 
can afford to buy ten or twelve transducers. 
What about the poor guys who can buy only 
one, and happen to end up with this last 20 
per cent? 
Dr. Konigsberg : You increase the price of a 
selected transducer by 20 per cent. This is what 
I was talking about. In short, what we're going 
to have to do is to use our pressure cycler, put 
an instrument in it, test it for a month. We will 
have to segregate those for stability, and, of 
course, we'll have to charge a premium price 
because we can't charge the same price and 
send it to some poor fellow who didn't know 
what he was buying. So what we will have to do 
then is select them and charge a premium 
price accordingly. We will give the worst trans- 
ducers to people who have students and let them 
be used for student experiments or acute ones. 
But I think that the only way is to have us pre- 
test them in a cyclic system for one month. 
As I say, we are doing that now when we have 
the data correlated, you understand, with the 
data in vivo. Now, I suspect this correlation will 
be very good for reasons that would take too 
much time to go into, but I do think that will 
be fair. I think it would be welcomed by people 
purchasing one transducer. 
D. B. Jackson, Abbott Laboratories, North 
Chicago : Do you have any information or feed- 
back about which telemetry system has had the 
most success with your transducers up to this 
point in time? 
Dr. Konigsberg: No, I do not. The ones I 
know of have been the units used by Franklin, 
some units that have been used with NASA 
