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A.w. Smith
05-09-1994, 11:57 PM
As promised, here are the responses I have recieved to date:

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>>> ORIGINAL POSTING:
>>>
>>> Dear BIOMCH-L Readers,
>>>
>>> Our laboratory has just received a donation of CAN$5,500.00
>>> (US$4,300.00) to be put towards an EMG system. From what I understand
>>> about the pricing of "commercial systems", I doubt very much if this
>>> amount would be enough to buy more than one or two channels.
>>>
>>> I have the details for an interesting system which I could arrange to
>>> have custom-built for our laboratory (8 channels = approx. CAN$4,000).
>>>
>>> I do have a couple of questions for interested readers:
>>>
>>> 1. Are there any good-quality, inexpensive EMG systems available
>>> commercially that would fit our budget (we d like at least 4-channels)?
>>>
>>> 2. If you were to have a system custom-built (or have done so
>>> recently), what features would you consider to be essential?
>>>
>>> If I receive any responses, I will post a synopsis.
>>>
>>> Thank you,
>>>
>>> Drew Smith, PhD
>>>
>>> ************************************************** **********************

Date: Tue, 3 May 1994
From: James.Ashton-Miller@um.cc.umich.edu

We built ourselves several 16 ch. W EMG systems five years ago for
about $3,500 ea. The specs for each were that it had to be
portable (12"8*"*5"), be powered by rechargeable batteries (NiCad),
have variable gain, output raw or RMS, have low noise (1-2uV), etc.
We have used them successfully for several years. The last series
of papers in which they were used are by Thelen G.T., Schultz, A.B.
and myself and are coming out in J. Biomech., J. Orthop. Res., etc
at the present time. These emanate from Darryl Thelen's thesis
on using system identification techniques to predict lumbar trunk
muscle activity in dynamic tasks.
..
James Ashton-Miller
~~~~~~~~~~~~~~~~~~~

From: "Mark D. Grabiner"
Date: Mon, 2 May 1994

Hi,
I have been using EMG amplifiers manufactured by a company named data,
Incorporated for about 12 years. The amplifier we use (their model 2124)
has performed very well and I would recommend that you investigate them for
your use. The company is located in Fort Collins Colorado (303) 493-1222
(don't give up on the phone number, eventually somebody does answer!). At
the time of our last purchase, the amps were about $600 US.

Mark

Date: Mon, 2 May 1994
From: drbaker+@pitt.edu (Dan Baker)
Subject: Re: Inexpensive EMG System Enquiry
Status: R

Drew,

Try contacting Chuck Wooley at the Center for Ergonomics at the University
of Michigan. He has built many and they are of good quality (I have had
very good luck w/ them as have several other researchers I know of). He
may be able to help you or at least point you in a good direction. His
phone number (actually the Center's phone number) is: (313) 763-2243.

Good luck,

Dan Baker, Ph.D.

drbaker+@pitt.edu

Musculoskeletal Research Center
Dept. of Orthopaedic Surgery
University of Pittsburgh

From: BECKETT@bim.msu.edu
Date: Mon, 2 May 1994

There is a company that makes a very small 8 channel emg system
for use in dentists office. It is designed for the study of temporal
mandibular joint disfunction. But we have used it successfully for
general emg use. It consists of an 8 channel external preamp box and
an 8 bit A/D board for and IBM PC /386 computer. It comes with some
good software but we have used the Preamp part and our own 12 bit A/d
boards and software for FFT and power analysis.

BioResearch
4113 North Port Washington Road
Milwaukee WI, 53212-1029

************************************************** ********************
Clifford L. Beckett MAIL ID: beckett@bim.msu.edu
System Designer
Material Science and Mechanics Department
Michigan State University VOICE: (517) 355-4659
E. Lansing, MI 48824 FAX: (517) 353-0789
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Date: Mon, 2 May 1994
From: Philip Schot

Dear Dr. Smith:

In response to your posting for cheap EMG support, I may have some info
you would find interesting.

We have 2 custom-built analog to digital devices with dedicated EMG channels
that might fall within your budget constraints. Here are some of the details:

It's called the DAS-416 (the FAA has purchased some upgraded systems based on
the units we currently use, and are very satisfied with the extremely low
cost and high performance).
1. Thru-put of 100 mHz (I believe), directly to hard disk,
so there is basically unlimited sampling time potential.
2. The 8 dedicated EMG channels are optically isolated for
subject safety, have very good impedence characteristics,
have additional programmable gains, and can be configured
for any physcial connections you may already use.
3. Ours also have 2 dedicated strain gauge channels and 5 raw
inputs (ie; no gains).
4. The system also provides an array of analysis software
(FFT, autocorr, derivatives).
5. The only drawback to the system is the manual labor
"intensiveness" to extract certain types of variables
(I forgot to mention some integral functions are also
provided).

The system is very well engineered, has some idiosyncracies, and does require
an IBM-compatible PC. I've been quite impressed with the device (and some
biomedical/industrial engineering-types have been very impressed). It is
menu driven, but definitely not "Windowsy"-- the developer likes Windows even
less than DOS!

Our complete units came in about $5000 (US), but there may be some savings
available if you were to limit the number of channels (and eliminating the
strain gauges might also cut some costs). If any of this sounds interesting,
please contact me and I'll put you in touch with the developer.

Sincerely,



:::::::::::::::::::::::::::::::::::::::::::
:: Philip Schot, Ph.D. ::
:: Biomechanics Lab Director ::
:: Department of Human Kinetics ::
:: University of Wisconsin - Milwaukee ::
:: P.O. Box 413 ::
:: Milwaukee, WI 53201 ::
:::::::::::::::::::::::::::::::::::::::::::
:: Phone: (414) 229-6080 ::
:: Fax: (414) 229-5100 ::
:: Email: pschot@alpha2.csd.uwm.edu ::
:::::::::::::::::::::::::::::::::::::::::::

Date: Mon, 2 May 1994
From: "Ronald Fredrick Zernicke"

Dear Dr. Smith,

You may wish to contact Boris Kacmar at

Bortec Electronics Inc.
P. O. Box 34147 #19
1200, 37th Street S.W.
Calgary, AB, T3C 1S2

PH: (403) 220-6275
FAX: (403) 283-8770

I just recently received a quote (and have ordered) the following
8-channel EMG system:

main receiving unit (19" standard rack mount unit)
patient unit
interconnection cable (35' long)
7 amplified electrodes
1 amplified electrode (with ground clip)
battery holder for two 9-volt batteries
belt with a pack for patient unit and battery holder
user's manual
(system comes with 1-yr warranty + CSA approval)

The price in CDN$ was $6380 (excl. GST). This is an excellent
system, yet relatively low-cost (it is currently being used in
Winnipeg for research and patient assessments).

Thus, for about $1000 more than you have (always the problem...),
you could get a very good 8-channel system. The 8-channel system
allows for future expansion to 16 channels.

Hope this information helps. Good EMG hunting...

Regards,

Ron Zernicke
(403) 220-8666
(403) 283-5666 (fax)
zernicke@acs.ucalgary.ca
Date: Mon, 2 May 1994
From: Graeme Wood

Hi Drew,

A couple of "leads" you might follow up on.

1) Moshe Solomonow's Biomedical Engineering Dept. at Loisianna State
University put together a 4 channel systme for me a couple of years ago.
I believe the going price is around $US5,000. It's a four channel
hard-wired system, but with miniaturized amplifiers which are located
immediately ajacent to the pick-up site.

2) Kit Vaughn told me not so long ago that he had a lead on a Californian
company that was custom producing cheap EMG telemetry systems. I believe
that Perry's group were using them as well, but Kit could tell you much more.

I'd be interested in the details of the Canadian system you have
unearthed. Is it the system being produced by one of Dave Winter's
ex-Technicians ? (If not, that's another lead for you).

All the best.

Graeme Wood

From: "Michel Ladouceur"
Organization: McGill University - P&OT
To: "A.W. Smith"
Date: Mon, 2 May 1994

:-)
:-)1. Are there any good-quality, inexpensive EMG systems available
:-)commercially that would fit our budget (we d like at least 4-channels)?
:-)
I think the system from the Boston Neuromuscular Foundation comes
very close to this price for an 8 channel system. However, the last
quotation I had in my hands were from at least 2 years ago.

:-)2. If you were to have a system custom- built (or have done so
:-) recently), what features would you consider to be essential?
:-)

I think it will depend on what movement and population you will be
doing EMG. But certainly, having pre-amps at the electrode site is a
must. When we took a look at other electrodes and compared them. We
got the impression that the ones from the Boston Neuromuscular
Foundation were the best electrodes available. We coupled them with
our own amplifiers. I think that was the cheapest solution.

I hope this will help you and if you have any questions on our setup
I will be glad to explain it in more details.

Have a nice day
************************************************** *******************
|Michel Ladouceur, MSc * Dans l'esprit humain, ainsi que dans |
|McGill University * l'univers, rien n'est en haut ni en bas; |
|School of P.& O.T. * tout se reclame egalement d'un centre |
|3630 Drummond, Room 105* commun qui manifeste une mysterieuse |
|Montreal (Quebec) * presence grace a l'harmonieux rapport de |
|H3G 1Y5 * toutes les parties a ce centre. |
| * |
|Tel: 514.398.4519 * J. W. von Goethe |
|Fax: 514.398.8193 ********************************************|
|e-mail: gsml@physocc.lan.mcgill.ca |
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Date: Wed, 4 May 1994
From: rreilly@elecmag3.ucd.ie (Richard Reilly)

Dear Drew,

I have put together EMG systems in the past, so the same reason that you are
considering doing so...cost.


What are you going to investigate, and on which muscle group...this will have
a bearing on the cost of the electrodes and also on the input stage of the
amplifiers.

Do you require this to interface with any particular device ie PC etc ?
What sampling rate do you require for each channel ?


Perhaps you could send me mail on these queries, as we may have developed a
system here at UCD.


Dr Richard Reilly
Dept of Electronic and Electrical Engineering,
University College Dublin,
Belfield,
Dublin 4, IRELAND

FAX : +353-1-2830921
TEL : +353-1-7061909

e-mail : rreilly@elecmag3.ucd.ie

and

The National Medical Rehabilitation Centre,
Lourdes Hospital
Dun Laoighaire,
Co. Dublin, IRELAND

Date: Wed, 4 May 1994
From: "Gary D. Heise"

Some may disagree, but I have found Therapeutics Unlimited in Iowa City,
Iowa to have the most reasonably priced, quality EMG equipment that is
commercially available. You must buy a power supply (1100 US$) and then
each EMG module (channel) is 900 US$ (includes amp and electrode). The
pre-amp is located in a housing with the electrode, so movement artifact
in wiring is minimized.

The phone number of Therapeutics Unlimited in Iowa is (319) 351-2435.
We have 6 channels of EMG from them and are impressed with the quality of
the equipment and the signal.

Good luck.
Gary Heise LSU

From:
To: awsmith@UTCC.UTORONTO.CA
Date: Wed, 4 May 1994

Hi Drew
I have recently purchased a custom made system with 16 channels
for approximately $3,600 CND. The company that makes them is run by a
Waterloo Kin Grad. I will be happy to give you his name and some
details.

Jim Potvin
School of Human Biology
University of Guelph
1-519-824-4120 ext. 4589


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