Thanks, Jon.  I am using the standard RCA type  connectors and plugs,=20
including the Y connector.  I have used the Y  connector for many years in=
 the=20
past with a split signal to the amp/filter board  and to a Omniscribe char=
t=20
recorder with no problems.
Regards,
Al
=20
=20
In a message dated 8/21/2009 6:18:32 P.M. Central Daylight Time, =20
jonfr@......... writes:

Hello.

The Y connector most likley does not carry the  frequancy that your sensor=
=20
is sending to the amp board.

Regards.
J=F3n  Fr=EDmann.

On f=F6s, 2009-08-21 at 18:34 -0400, AHrubetz@....... wrote: =20
Some months ago  I purchased a Geotech Instruments Helicorder RV-301B with=
=20
the  accompanying amplifier AR-320B.  It works just fine when I drive it=
 =20
using one channel from one of Larry's older amp/filter boards.  The  input=
 is=20
from a Lehman-type horizontal detector utilizing a coil  with 8k resistanc=
e.=20
(hz1 detector).     =20



I normally have  the Lehman hz1 output going into a second, newer version=
=20
of  Larry's amp/filter A/D boards, and then on  to WinSDR.  =20



Here is my  problem:  I want to split the output from hz1 using a Y=20
connector to  both the WinSDR display and the helicorder so I can record=
 analog and=20
 digital simultaneously.  When I do this, the helicorder stylus goes  dead=
=20
and the CRT display from the amp/filter/AD board displays rhythmic =20
amplitude spiking.  There appeared to be an impedance  mismatch, so  an EE=
 designed=20
a buffer amplifier for me with two  outputs.  Unfortunately, when using th=
e=20
buffer amp, the helicorder  stylus still is inoperative and the spiking=20
again shows up on the CRT  display from the amp/filter/AD board, just as=
 before.=20
=20



I am at a  loss at what to try next.  The Geotech Instrument people say=20
they  are too busy to give me any advice.  I am wondering if any of you us=
ing =20
the RV301B helicorder has tried to use a split signal such as I  described=
? =20
I would appreciate any suggestions from the PSN  family.=20

Thanks and  regards,=20



Al  Hrubetz=20

Dallas,  Texas=20






=20
____________________________________








Thanks, Jon.  I am using the standard RCA=
 type=20
connectors and plugs, including the Y connector.  I have used the Y=
=20
connector for many years in the past with a split signal to the amp/filter=
 board=20
and to a Omniscribe chart recorder with no problems.
Regards,
Al
 

In a message dated 8/21/2009 6:18:32 P.M. Central Daylight Time,=20
jonfr@......... writes:
Hello.

The Y connector most likley does not carry th=
e=20
  frequancy that your sensor is sending to the amp board.

Regards.<=
BR>J=F3n=20
  Fr=EDmann.

On f=F6s, 2009-08-21 at 18:34 -0400, AHrubetz@........
 wrote:=20
  
Some=
 months ago=20
    I purchased a Geotech Instruments Helicorder RV-301B with the=20
    accompanying amplifier AR-320B.  It works just fine when I drive=
 it=20
    using one channel from one of Larry's older amp/filter boards. =
 The=20
    input is from a Lehman-type horizontal detector utilizing a=
 coil=20
    with 8k resistance. (hz1 detector).    =20
  

  

  
I norm=
ally have=20
    the Lehman hz1 output going into a second, newer versio=
n of=20
    Larry's amp/filter A/D boards, and then on=20
    to WinSDR.   
  

  
Here=
 is my=20
    problem:  I want to split the output from hz1 using a Y connector=
 to=20
    both the WinSDR display and the helicorder so I can record analog and=
=20
    digital simultaneously.  When I do this, the helicorder stylus go=
es=20
    dead and the CRT display from the amp/filter/AD board displays rhythmi=
c=20
    amplitude spiking.  There appeared to be an impedance=
=20
    mismatch, so  an EE designed a buffer amplifier for me with=
 two=20
    outputs.  Unfortunately, when using the buffer amp, the helicorde=
r=20
    stylus still is inoperative and the spiking again shows up on the CRT=
=20
    display from the amp/filter/AD board, just as before.=20
  

  

  
I am=
 at a=20
    loss at what to try next.  The Geotech Instrument people say=
 they=20
    are too busy to give me any advice.  I am wondering if any of you=
 using=20
    the RV301B helicorder has tried to use a split signal such as I=20
    described?  I would appreciate any suggestions from the PSN=20
    family. 
  
Thanks=
 and=20
    regards, 
  

  
Al=20
    Hrubetz 
  
Dallas=
,=20
    Texas 
  

  
 =
=20