Xformer: 15ohm to 600ohm - use for?

[redrabbit]

I picked up a pair of these audio xformers....

Z=15 ohm Primary
Z=600 ohm Secondary

(four pins total (no ct))

HP 9120-0018
DC current = 0
Power Level 1MW
MFD by Paeco 2016

-pulled from some unknown HP gear???
They're about 1.5" square, by 2.25" high

What use do these have ?

thx,
=RR=

[mobyd]

Originally posted by redrabbit
I picked up a pair of these audio xformers....

Z=15 ohm Primary
Z=600 ohm Secondary

(four pins total (no ct))

HP 9120-0018
DC current = 0
Power Level 1MW
MFD by Paeco 2016

-pulled from some unknown HP gear???
They're about 1.5" square, by 2.25" high

What use do these have ?

thx,
=RR=

Ribbon Mic ? MC cartridge ?
M

[AndrewT]

Hi,
very low impedance mic seems to make sense.
step up ratio = root(40)=6.3times.
note zero DC!


Way off bat, could it have been for a dynamic strain gauge?

[cpemma]

"This low profile 1:1 600Ω transformer is designed to provide isolation between modems or similar devices and telephone lines." but the two BABT ones sold by Rapid are both 1:1.

The first of these can be rigged for 600Ω:15Ω but "Each transformer is constructed with dual windings on the primary and secondary providing a wide range of impedance matching ratios to suit many input, interstage and output applications" so I guess it's a case of first find an application.

A megawatt (1MW) sounds good for such a small package, must be this new ferrite & superconductor stuff.

[redrabbit]

so I guess it's a case of first find an application.

OK!!!!
any links to a suitable project?

=RR=

[AndrewT]

Hi,

A megawatt (1MW)

seem to be a common mis-application of the capitalised multilier by a few manufacturers.

It seems to be more prevalent West of the Atlantic where metric is not adopted, yet

The rule is simple;-
all multipliers above k are upper case,
all multipliers from k and downwards are lower case.

The problem crops up repeatedly with capacitors but the 10^9 error is usually obvious.
Where a bigger problem exists is mis-using m for micro rather than u. This error is only a factor of 10^3 and confusion is very possible.

Please reserve m for milli, u for micro amd M for mega.

[Christer]

Originally posted by AndrewT

Please reserve m for milli, u for micro amd M for mega.

I wholeheartedly agree and hate when people write mHz instead of MHz etc. However, do take note of one thing that matters to everbody using the Spice simulator. It doesn't distinguish between upper and lower case, so it treats both "m" and "M" as milli, and you must write "meg" when you mean mega. I don't know how many times I have forgotten that and scratched my head when getting strange results.
(Maybe there are versions of Spice that deviate from the standard, though, and allows M for mega. Check you local Spice.)

[cpemma]

Originally posted by Christer
...the Spice simulator. It doesn't distinguish between upper and lower case, so it treats both "m" and "M" as milli, and you must write "meg" when you mean mega. I don't know how many times I have forgotten that and scratched my head when getting strange results.

Thanks for that info, I've been using 1000k for 1M as a workround.

all multipliers above k are upper case

And k, although flouting the rule >1=upper, was made lower case to avoid confusion with K for Kelvin. Useless information but could be a good chat-up line with the right lady.