[time-nuts] Pins of ERC Precision Crystal Oscillator EROS-800-NTL-5 OCXO
radio.n9xr at gmail.com
Sun Jun 14 22:30:53 EDT 2015
The EROS-800 versions had no EFC. Only the EROS-750 versions had EFC.
On Sun, Jun 14, 2015 at 10:26 AM, Bob Camp <kb8tq at n1k.org> wrote:
> Best guess is that the 4 pins are:
> An ohm meter is your friend in this case.
> Ground should be shorted to the case.
> Output should be DC blocked (as in > 1 meg ohm)
> EFC should be something like 100K or so to ground
> Power should have a fairly big cap on it, the ohm meter will go up in
> resistance slowly.
> In some cases the output has an attenuator (pad) on it. That will give you
> something like
> < 300 ohms (but not a short) to ground. The EFC might be any impedance
> from 10K on up.
> If your ohm meter will read capacitance, that’s a great way to spot the
> input capacitor on the
> power pin. The EFC may have a bypass, but the power pin should have a much
> larger one.
> Once you have that worked out, check your results:
> Apply power through a 1K ohm resistor. It should come up to a a few volts
> (< 8V). Don’t
> leave it in this condition for long. You are simply trying to make sure
> you have EFC
> and power straight. If you apply +12 to the EFC through 1K, it will go up
> to roughly
> 12V. The same is true applying power through 1K to a DC blocked output
> Now apply +12 to the power pin with a current limited supply. It should
> pull less than 1A.
> If it does, leave it on power and see if there is an output. If it’s got
> an output, you have
> things worked out correctly. If it has no output then either you have the
> pins wrong or the unit
> is defective.
> Good Luck! This is not a prefect way to do it, but it works in about 90%
> of the cases. It’s fairly
> safe in this case. You already know that the power supply is +12V.
> > On Jun 14, 2015, at 5:41 AM, Mod Mix <modmix at t-online.de> wrote:
> > Hi,
> > got an ERC Precision Crystal Oscillator EROS-800-NTL-5 OCXO 9.9000000
> MHz +12V RF (ebay item no. 140779678375).
> > Can not find any data sheet to see which of the four pins is used for
> what, though.
> > Any help would be much appreciated.
> > TIA
> > Ulli
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