When is a MAR-6 not a MAR-6?

[G3GJA]

John G6VLT at Mainline has kindly refunded my purchase and here is his response:

Hello Clive

My name is John, for my sins I own Mainline Electronics and have been selling parts
to Radio guys all my life it seems.

I picked up on your message to Roxanne about this mar6 part and just want give you a bit further
information as for me it's interesting on many points

I looked at the reel of this part and its marked with the Mini-Circuits label as a MAR-6sm
and on the reel its says on the Mini circuits label marked as A06, I tried to verify what
you had written which I believe is 100% accurate, just now they have put a new data sheet on their
site and now the part seems to have a higher spec and MAR6-SM+ what the + means I have no idea

So this is a real mystery to us, I was peeved no end when someone can make a note on a website
saying we are selling possible duff stuff and don't even take the time to contact us in the first
place to resolve the problem, I am also a ham G6VLT though was on a lot longer than my call so I know
what a pain it is to build 23cms stuff and find it does not work as test equipment is always
hard to find.

We bought these parts in a large parcel from a Magor Nortel sub-contractor so never assumed it would
be a problem as they came off their reeling and production machines.

I can only think that the parts have been re-reeled by some Chinese outfit who also made a new label
or this OEM was using the other part and they offered this (that's doubtful) or Mini-Circuits made
a boob or used another part to cover a production shortfall, I have never Known Mini-Circuits to sell
a duff part in all my years, so thinking is its some copy part from China.

I am responsible for this, so we put a note on EBay but will pull this part and relist it under the Msa-0686
old Avantek part and try and obtain a new source of Mar-6 , I have left instructions that any one that
needed or has had a problem with the parts can have their money refunded.

We use to sell a lot of radio kits I am interested if these transverter
boards are available as maybe we can do this again as there are still a
few people building products.

Thank you very much for bringing this to my attention and if you can
post this reply on the same site it would be welcomed

John Higgins
Mainline
G6VLT

[G4OHV]

I got this email also, after sending a complaint, and also a refund for the parts bought off Ebay.

Got genuine ones from JAB Electronics

Regards

Col

[G3GJA]

How do the real MAR-6 perform? I'd be very interested to know Col.

I'm currently using MSA-0886 on both the 70cm & 23cm versions and can get about +2dBm and -5dBm respectively with mod and around 8dB more without. I find if I push it a bit more then the regrowth becomes unacceptable.

I've also tried the SP5043 amp from G4DDK and can add another 10dB with that before regrowth kicks in again so not really sucessful. It's beginning to look as though you have to keep the 'nose' of the output as seen on the SA about 10dB below the rated P1dB compression point of the device.

Clive

[G1LWX]

I see that mainline are now advertising on Ebay the proper MAR-6 by mini-circuits .

[G3GJA]

As per the thread here: http://www.batc.org.uk/forum/viewtopic. ... 0&start=10 it may be better to consider using a MSA-0886; it has a much higher output before compression kicks in if you are prepared to fiddle with the bias & supply.

[w0fms]

The "+" in Mini-Circuits terminology is usually an indication of RoHS but in some cases it also signals small performance differences/enhancements.

Fred W0FMS