Hi Jim,

We have been thinking about a vertical version of the VolksMeter for =
some time.  The differential capacitive sensor would work fine in a =
vertical, as would the pivot technology and the eddy damper.  The =
problem, as has been much talked about here, is cost-effective thermal =
compensation for the spring.  A vertical VolksMeter needs to be as =
precise (and maintenance-free) as the current horizontal instrument.  =
While force-feedback would work, it would likely be too costly for the =
VolksMeter market niche ($1000-$2000 selling price).  Dr. Peters, the =
brains behind the VolksMeter, has been looking into a bi-metal strip =
that would add tension to the spring as the temperature goes up (and the =
spring otherwise lengthens) but, as you might imagine, designing a =
bi-metal strip that exactly compensates the spring is a challenge.  Zero =
tc springs are possible, but too costly in the volumes we need.

Designing a product for production is always an exercise in tradeoffs =
and compromises.   I would welcome any suggestions.

Regards,

Les LaZar
RLL Instruments / a division of Zoltech Corporation
818-780-1800
  ----- Original Message -----=20
  From: Jim ODonnell=20
  To: psn-l@.................
  Sent: Friday, July 24, 2009 6:53 PM
  Subject: Re: which seismometer?


  Hi All-
  Observations of the RLL:
  For the last year I have been comparing Larry=92s sensors to his RLL =
(Volksmeter-  .lctst & .lctst1) and the results are rather outstanding.  =
I live close to Las Vegas so record mostly local events with 1 Hz & 4.5 =
Hz geophones.  But I have been considering the RLL as it gets them =
all=85.Local, Regional, & Teleseismic.
  It is a Horizontal & I like to look at Rayleigh waves which are =
predominately Z.
  Any chance of a RLL in Z???
  <<<<    Jim

  Jim O'Donnell- Geophysical Consultant/Contractor
  Geotechnical/Geothermal/Oil & Gas/Mining Applications
  Seismic Surveys- Surface Waves, Refraction, & Reflection
  Ground Penetrating Radar, Resistivity, Magnetic, & VLF-EM Surveys
  Geophysics@..........  702.293.5664  702.281.9081 cell  =20
  Boulder City, NV


  ---------- Original Message ----------
  From: "Les LaZar" 
  To: 
  Subject: Re: which seismometer?
  Date: Fri, 24 Jul 2009 16:36:01 -0700

  Hi Jay,

  At the risk of tooting my own horn...

  If your budget is flexible, you don't specifically need a Lehman type =
design=20
  and your application would benefit from a research-quality instrument, =
you=20
  may wish to consider the RLL Instruments VolksMeter II (=20
  http://www.rllinstruments.com ).  Many of these are currently being =
used in=20
  educational and research applications.  Some are in use by psn =
members.

  If you are interested, I would be happy to answer any questions you =
might=20
  have.

  Regards,

  Les LaZar
  RLL Instruments / a division of Zoltech Corporation
  818-780-1800

  ----- Original Message -----=20
  From: "Jay Muza" 
  To: 
  Sent: Friday, July 24, 2009 2:23 PM
  Subject: which seismometer?


  Hi
  I would like to purchase one of the inexpensive Lehman type =
seismometers=20
  currently on the market.  The three I am considering are the AS-1, the =
UK=20
  School of Seismology SEP Seismometer System, and the Rockwave HS-3.  =
Any=20
  guidance..any at all...would be greatly appreciated.  Thank you.


  Dr. Jay Muza
  Department of Physical Sciences
  Broward College
  Davie, FL  33314

  Office: 954.201.6771
  Cell:    954.736.8231

  jmuza@...........

  Please Note: Due to Florida's very broad public records law, most =
written=20
  communications to or from College employees regarding College business =
are=20
  public records, available to the public and media upon request. =
Therefore,=20
  this email communication may be subject to public disclosure.

  Please consider the environment before printing this email.

  __________________________________________________________

  Public Seismic Network Mailing List (PSN-L)

  To leave this list email PSN-L-REQUEST@.............. with
  the body of the message (first line only): unsubscribe
  See http://www.seismicnet.com/maillist.html for more information.



  __________________________________________________________

  Public Seismic Network Mailing List (PSN-L)

  To leave this list email PSN-L-REQUEST@.............. with=20
  the body of the message (first line only): unsubscribe
  See http://www.seismicnet.com/maillist.html for more information.








Hi Jim,
 
We have been thinking about a vertical =
version of=20
the VolksMeter for some time.  The differential capacitive sensor =
would=20
work fine in a vertical, as would the pivot technology and the eddy=20
damper.  The problem, as has been much talked about here, is=20
cost-effective thermal compensation for the =
spring.  A=20
vertical VolksMeter needs to be as precise (and maintenance-free) as the =
current=20
horizontal instrument.  While force-feedback would work, it would =
likely be=20
too costly for the VolksMeter market niche ($1000-$2000 selling =
price). =20
Dr. Peters, the brains behind the VolksMeter, has been looking into a =
bi-metal=20
strip that would add tension to the spring as the temperature goes up =
(and the=20
spring otherwise lengthens) but, as you might imagine, designing a =
bi-metal=20
strip that exactly compensates the spring is a challenge.  Zero tc =
springs=20
are possible, but too costly in the volumes we need.
 
Designing a product for production is =
always an=20
exercise in tradeoffs and compromises.   I would welcome =
any=20
suggestions.
 
Regards,
 
Les LaZar
RLL Instruments / a division of Zoltech =

Corporation
818-780-1800

  
----- Original Message ----- 
  From:=20
  Jim=20
  ODonnell 
  
To: psn-l@.............. 
  
Sent: Friday, July 24, 2009 =
6:53 PM
  
Subject: Re: which =
seismometer?
  


  
Hi All-
Observations of =
the RLL:
For=20
  the last year I have been comparing Larry=92s sensors to his RLL=20
  (Volksmeter-  .lctst & .lctst1) and the results are =
rather=20
  outstanding.  I =
live=20
  close to Las Vegas so record mostly local events with 1 Hz & =
4.5 Hz=20
  geophones.  But I have =
been=20
  considering the RLL as it gets them all=85.Local, Regional, &=20
  Teleseismic.
It is a Horizontal & I like to look at Rayleigh =
waves=20
  which are predominately Z.
Any chance of a RLL in=20
  Z???
<<<<    Jim

Jim =
O'Donnell-=20
  Geophysical Consultant/Contractor
Geotechnical/Geothermal/Oil & =

  Gas/Mining Applications
Seismic Surveys- Surface Waves, Refraction, =
&=20
  Reflection
Ground Penetrating Radar, Resistivity, Magnetic, & =
VLF-EM=20
  Surveys
Geophysics@..........  702.293.5664  702.281.9081 =
cell=20
    
Boulder City, NV


---------- Original =
Message=20
  ----------
From: "Les LaZar" =
<llazar@..................>
To:=20
  <psn-l@..............>
Subject: Re: which =
seismometer?
Date: Fri,=20
  24 Jul 2009 16:36:01 -0700

Hi Jay,

At the risk of =
tooting my own=20
  horn...

If your budget is flexible, you don't specifically need =
a=20
  Lehman type design 
and your application would benefit from a=20
  research-quality instrument, you 
may wish to consider the RLL =
Instruments=20
  VolksMeter II ( 
http://www.rllinstruments.com ).  Many of =
these are=20
  currently being used in 
educational and research applications. =
 Some=20
  are in use by psn members.

If you are interested, I would be =
happy to=20
  answer any questions you might 
have.

Regards,

Les=20
  LaZar
RLL Instruments / a division of Zoltech=20
  Corporation
818-780-1800

----- Original Message ----- =

From: "Jay=20
  Muza" <jmuza@...........>
To: =
<psn-l@..............>
Sent:=20
  Friday, July 24, 2009 2:23 PM
Subject: which=20
  seismometer?


Hi
I would like to purchase one of the =
inexpensive=20
  Lehman type seismometers 
currently on the market.  The three =
I am=20
  considering are the AS-1, the UK 
School of Seismology SEP =
Seismometer=20
  System, and the Rockwave HS-3.  Any 
guidance..any at =
all...would be=20
  greatly appreciated.  Thank you.


Dr. Jay =
Muza
Department of=20
  Physical Sciences
Broward College
Davie, FL =
 33314

Office:=20
  954.201.6771
Cell:=20
     954.736.8231

jmuza@...........

Please =
Note:=20
  Due to Florida's very broad public records law, most written=20
  
communications to or from College employees regarding College =
business are=20
  
public records, available to the public and media upon request. =
Therefore,=20
  
this email communication may be subject to public=20
  disclosure.

Please consider the environment before printing =
this=20
  =
email.

__________________________________________________________<=
BR>
Public=20
  Seismic Network Mailing List (PSN-L)

To leave this list email=20
  PSN-L-REQUEST@.............. with
the body of the message (first =
line=20
  only): unsubscribe
See http://www.seismicnet.com/maillist.html for =
more=20
  =
information.



_____________________________________________=
_____________

Public=20
  Seismic Network Mailing List (PSN-L)

To leave this list email=20
  PSN-L-REQUEST@.............. with 
the body of the message (first =
line=20
  only): unsubscribe
See http://www.seismicnet.com/maillist.html for =
more=20
  information.