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Re: [time-nuts] Normal operating specs of a Morion MV89?

DM
Dave M
Wed, Sep 28, 2016 5:05 PM

From my experience, your best  and cheapest approach is to contact the

seller and see if they will just send you a replacement.  If the seller
won't cooperate, and insists that you return the item, just close the issue
and try to repair it, or buy another one.  If you bought the MV89 from an
Ebay seller, Ebay will require that you return the item by a traceable
shipment, which will probably cost you more than the MV89 cost.

Sorry to say that, but that's just the dimmer side of buying unknown items
from across the big pond.

Dave M

Tim Lister wrote:

On Wed, Sep 28, 2016 at 4:14 AM, Bob Camp kb8tq@n1k.org wrote:

Hi

You have one of the many MV89A’s with an output problem. To be
absolutely
sure of the output, you need to have the scope set to 50 ohm input.
If it was set to Hi-Z, the output is likely even lower…..

It seems that the scope is 1 MOhm input impedance and is not
changeable. I will have to see if we have any 50 Ohm in-line
terminators around that I can also borrow. Does anyone think that
there is any value in trying to pursue a return and replacement with
the ebay seller (being China, it's likely to be a long round-trip time
for both messages and parcels) or just live with it and move on
(potentially replacing the capacitor later if I get some way of
getting the casing open safely). From what Bob and others have said,
it seems that most of the MV89's have this problem so it seems
unlikely I would get a better one without a lot of trials.

Tim

Bob

>From my experience, your best and cheapest approach is to contact the seller and see if they will just send you a replacement. If the seller won't cooperate, and insists that you return the item, just close the issue and try to repair it, or buy another one. If you bought the MV89 from an Ebay seller, Ebay will require that you return the item by a traceable shipment, which will probably cost you more than the MV89 cost. Sorry to say that, but that's just the dimmer side of buying unknown items from across the big pond. Dave M Tim Lister wrote: > On Wed, Sep 28, 2016 at 4:14 AM, Bob Camp <kb8tq@n1k.org> wrote: >> Hi >> >> You have one of the many MV89A’s with an output problem. To be >> absolutely >> sure of the output, you need to have the scope set to 50 ohm input. >> If it was set to Hi-Z, the output is likely even lower….. > > It seems that the scope is 1 MOhm input impedance and is not > changeable. I will have to see if we have any 50 Ohm in-line > terminators around that I can also borrow. Does anyone think that > there is any value in trying to pursue a return and replacement with > the ebay seller (being China, it's likely to be a long round-trip time > for both messages and parcels) or just live with it and move on > (potentially replacing the capacitor later if I get some way of > getting the casing open safely). From what Bob and others have said, > it seems that most of the MV89's have this problem so it seems > unlikely I would get a better one without a lot of trials. > > Tim > >> >> Bob