[Milsurplus] Texscan LA-70 attenuator?

[antqradio at sbcglobal.net]

To have the lowest VSWR or highest Return Loss, any attenuator must match the transmission line's impedance.  Any mismatch between the transmission line's and attenuator's impedance would reflect a portion of the RF signal back to either the generator or load depending on the degree of mismatch.
Measure either the input or output of the attenuator with an ohmmeter.  A 50 ohm attenuator will measure very close to 50 ohms resistance.  Likewise, a 75 ohm attenuator will measure very close to 75 ohms resistance.  The higher the attenuator's value, the closer it's resistance value will be to the transmission line's impedance.  
This is assuming that the attenuator has not been subjected to a higher then rated power level that would change either or both of the attenuator's series or shunt resistor values.Jim

      From: Hubert Miller <Kargo_cult at msn.com>
 To: "tetrode at googlegroups.com" <tetrode at googlegroups.com>; "Manual_Exchange at yahoogroups.com" <Manual_Exchange at yahoogroups.com>; "milsurplus at mailman.qth.net" <milsurplus at mailman.qth.net> 
 Sent: Monday, October 17, 2016 1:20 AM
 Subject: [Milsurplus] Texscan LA-70 attenuator?
   
 <!--#yiv1193965470 _filtered #yiv1193965470 {font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;} _filtered #yiv1193965470 {font-family:Calibri;panose-1:2 15 5 2 2 2 4 3 2 4;}#yiv1193965470 #yiv1193965470 p.yiv1193965470MsoNormal, #yiv1193965470 li.yiv1193965470MsoNormal, #yiv1193965470 div.yiv1193965470MsoNormal {margin:0in;margin-bottom:.0001pt;font-size:11.0pt;font-family:"Calibri", sans-serif;}#yiv1193965470 a:link, #yiv1193965470 span.yiv1193965470MsoHyperlink {color:#0563C1;text-decoration:underline;}#yiv1193965470 a:visited, #yiv1193965470 span.yiv1193965470MsoHyperlinkFollowed {color:#954F72;text-decoration:underline;}#yiv1193965470 span.yiv1193965470EmailStyle17 {font-family:"Calibri", sans-serif;color:windowtext;}#yiv1193965470 .yiv1193965470MsoChpDefault {font-family:"Calibri", sans-serif;} _filtered #yiv1193965470 {margin:1.0in 1.0in 1.0in 1.0in;}#yiv1193965470 div.yiv1193965470WordSection1 {}-->I know this is a long shot. This attenuator has BNC in and out; 0-10 db step switch in 1 db increments. No other marking but LA-70 and Texscan and date code 9610.  I can find one to buy on the net, but NO specs listed for it. Anyone have a GOOD clue, like 52 or 72 ohms? tnx- Hue 
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