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    PAS 2 Got a Sister

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    rodneyk915

    Posts : 16
    Join date : 2016-08-29

    PAS 2 Got a Sister

    Post by rodneyk915 on Tue Sep 20, 2016 2:49 pm

    I think I may have caught the bug  Shocked I already had a PAT 4 for years then got the PAS 2 recently and now this FM 1 I got the other day. It powers up but the blue eye wasn't blue and there wasn't any sound. Took the shielding off of all the tubes and they were lit except the rectifier but if you look at the tube, it is smoked so I have another on the way and then I will try again. These were taken moments after unboxing prior to cleaning and plugging in. Not sure where that piece of shielding goes that was lying loose unless it was supposed to be part of the shield around the rectifier.




    Peter W.

    Posts : 85
    Join date : 2016-08-07
    Location : Melrose Park, PA

    Re: PAS 2 Got a Sister

    Post by Peter W. on Tue Sep 20, 2016 3:43 pm

    The rectifier is unshielded on the FM1 & 3. However, other than the EM80 eye tube for a 1, all the others are shielded. Note that the tube bases have a small metal tongue that friction-connects to the shield when it is slipped over the tube down to the base.

    The FM1S & the FM3 use the EMM801 dual eye tube. That, as it happens, is very nearly unobtanium these days. Technically, you have an FM1S as it has the stereo board. Count yourself lucky.

    That bit of metal looks like scrap.

    GP49

    Posts : 718
    Join date : 2009-04-30
    Location : East of the sun and west of the moon

    Re: PAS 2 Got a Sister

    Post by GP49 on Tue Sep 20, 2016 6:51 pm

    Won't work at all without a functioning rectifier. Don't give up on your EMM801 eye tube yet.

    I got the last new one Dynaco had...so said the note accompanying it, from Bob Tucker!

    rodneyk915

    Posts : 16
    Join date : 2016-08-29

    Re: PAS 2 Got a Sister

    Post by rodneyk915 on Tue Sep 20, 2016 7:48 pm

    Thanks for the info. I was happy to see the eye tube light up, I had read they were pretty much impossible to replace. Should have the rectifier by the weekend then I'll give it another go.

    Dave_in_Va

    Posts : 129
    Join date : 2013-04-02

    Re: PAS 2 Got a Sister

    Post by Dave_in_Va on Tue Sep 20, 2016 9:30 pm

    This must be why I have trouble selling books on eBay these days. Nobody even looks anymore.

    There are several EMM801 tubes on listed there now. Not that expensive.

    Pretty complicated looking guts in that tube!

    GP49

    Posts : 718
    Join date : 2009-04-30
    Location : East of the sun and west of the moon

    Re: PAS 2 Got a Sister

    Post by GP49 on Tue Sep 20, 2016 9:46 pm

    rodneyk915 wrote:Thanks for the info. I was happy to see the eye tube light up, I had read they were pretty much impossible to replace. Should have the rectifier by the weekend then I'll give it another go.

    There are no more new ones (officially...there are probably some in private hands, or in unbuilt FM-3 kits). Used ones are out there, from scrapped FM-3s.

    eickmewg

    Posts : 38
    Join date : 2014-08-29

    Re: PAS 2 Got a Sister

    Post by eickmewg on Wed Sep 21, 2016 8:04 am

    I got a supposedly NOS EMM801 from an eBay seller for $40 awhile back. It came in a pristine, properly labelled Telefunken tube box with perfect lettering on the tube so it sure looked NOS. So, they are out there if you keep your eyes open. The new tube was considerably brighter than the old tube.

    Peter W.

    Posts : 85
    Join date : 2016-08-07
    Location : Melrose Park, PA

    Re: PAS 2 Got a Sister

    Post by Peter W. on Wed Sep 21, 2016 8:26 am

    I have two NIB spares that I got from a rather prestigious audio sales/service shop back in the day when the owner retired. A friend and I helped him move out, and also helped him sell off his attic inventory via our friends and acquaintances. This was over 30 years ago, and the stuff in that attic was then considered useless. Today, not so much.

    As our 'reward', he allowed us to divide his tube stock for $1 per tube irrespective of type, brand and so forth. There were four EMM801s. NOTE: in the years since and across MANY FM3s, I have never yet had the need to use one. Most are stripped of their 12AX7s, but not of the eyes.

    Peter W.

    Posts : 85
    Join date : 2016-08-07
    Location : Melrose Park, PA

    Re: PAS 2 Got a Sister

    Post by Peter W. on Wed Sep 21, 2016 9:54 am

    By the way, you can always go solid-state on the rectifier. The cap would be a 0.10 uF @ 600V.

    http://s213.photobucket.com/user/flemingmras/media/Cycle1.jpg.html

    There are any number of configurations, but this is one I have used.

    peterh

    Posts : 643
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: PAS 2 Got a Sister

    Post by peterh on Wed Sep 21, 2016 11:05 am

    Rodney,
    the rectifier is a 6v4 / EZ80. I have in stock, but that won't help you i suppose.
    As already mentioned you can replace the ez80 with 2 1n4007 diodes ( or un4007) ,
    this could be done temporarily to check out the rest.

    rodneyk915

    Posts : 16
    Join date : 2016-08-29

    Re: PAS 2 Got a Sister

    Post by rodneyk915 on Sat Sep 24, 2016 2:39 pm

    Thanks for the info and suggestions. I got the rectifier a little while ago and put it in and everything is working perfectly now  cheers


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