[time-nuts] 10 MHz Filters

[Richard Solomon]

No problem, always glad to be of help to those in need.

73 es HH, Dick, W1KSZ


On 12/2/2014 2:27 PM, John Ackermann N8UR wrote:
> Thanks for the kind words, Dick. :-)
>
> However, a couple of notes on the TADD-1 bandpass filter:
>
> 1.  I *don't* recommend installing it unless there is a good reason.  
> As others have noted, any tuned circuit is a thermometer and will 
> degrade ADEV performance.  Other than the original test unit, I 
> haven't built the filter into any of the several TADD-1s I've deployed 
> in my lab.
>
> 2.  The component values for the example filter in the TADD-1 manual 
> are wrong.  I haven't gotten around to fixing that, mainly because of 
> point 1.
>
> And since the topic of isolated grounds has come up: the TADD-1 uses 
> transformer isolation on each input and output, and provides DC 
> isolation by putting a 10nf cap between ground and the coax shield 
> (with a very short path).  This seems to have worked pretty well for 
> most users.
>
> John
> ----
>
> On 11/27/2014 11:41 AM, Richard Solomon wrote:
>> If you want to see how to really do it right, check out this
>> distribution Amp
>> on the TAPR site.
>>
>> https://www.tapr.org/kits_tadd-1.html
>>
>> 73, Dick, W1KSZ
>>
>>
>> On 11/26/2014 9:08 PM, Perry Sandeen via time-nuts wrote:
>>> List,
>>>
>>>
>>> I have seen on the net a 10 MHz filter using 10.7 IFtransformers but
>>> have no idea how well they would work for isolation with thenew style
>>> Lucent boxes.
>>>
>>>
>>> Thoughts?
>>>
>>>
>>> On Ebay venders are offering 10 MHz crystals for almostnothing if you
>>> buy 30.  My question wouldthese be good for making some type of simple
>>> ladder filter?
>>>
>>>
>>> In his article *Modifying Lucent RFG-M-RB Rubidium FrequencyStandard*
>>> the author used a 10MHz filter that was taken from an old
>>> 10MbitEthernet LAN board. The part number he used was 20F001N and I
>>> found them onEbay for low prices.
>>>
>>>
>>> Now I don’t have any access to any old ethernet LAN boardsso I’d have
>>> to build from scratch.
>>>
>>>
>>> Does anyone of these methods have an advantage over theothers on the
>>> new style Lucent boxes or in the making of a small
>>> distributionamplifier with good isolation?
>>>
>>>
>>> Regards,
>>>
>>>
>>> Perrier
>>>
>>>
>>> _______________________________________________
>>> time-nuts mailing list -- time-nuts at febo.com
>>> To unsubscribe, go to
>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>> and follow the instructions there.
>>>
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at febo.com
>> To unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to 
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>