[R-390] Orange Drop vs ceramic disc

rbethman rbethman at comcast.net
Fri Apr 1 09:39:54 EDT 2011


OKAY, just my $0.02 worth.

We are talking about R-390A/URRs that *have* BBODs.  My experience has 
been that the pre '67 EACs have BROWN BODs.  Such as the '51 contract 
Collins Blue-Striper I'm restoring.

I've finally located the nasty caps under the RF deck.  I had problems 
identifying them based on color photos, and discoloration of components 
from heat.

Looking at this from a "practical" aspect, I don't care to use Orange 
Drops per se.  They are TOO large and a pain to use.

Now that that is tossed out there, the SP-600 I got in trade in 2004 for 
my '67 EAC, HAS been recapped underneath with ORANGE DROPS!

I have been running it pretty constantly.  There have been NO issues.  
My ears are still *real* good.  Why, I have no idea.  I'm NOT an 
Audiophile, BUT I can hear when there is distortion.  I only here it on 
a very strong station that you have to start reducing the RF gain, AND 
the volume.

I've been using some kind of film caps to recap the Collins.  They 
aren't ODs.

I *think* this is really getting blown out of proportion!

I'd have to ask Barry if having used ODs - "Do you notice ANY degradation?"

Bob - N0DGN

On 4/1/2011 8:54 AM, Cecil Acuff wrote:
> I think it's important to also mention...there are two different type of
> Orange Drop caps.  Can't remember the designations without the catalog in
> front of me but...there are.  I think one is metalized film and the other
> film/foil types....am I off track here?
>
> We need to make sure we don't direct folks using the Orange Drop terminology
> in a blanket fashion.  As I remember one is recommended and the other not so
> much.
>
> I'll have to pull the catalog to fill in the blanks if someone else doesn't
> chime in...
>
> Cecil
> ----- Original Message -----
> From: "Barry"<n4buq at knology.net>
> To:<R-390 at mailman.qth.net>
> Sent: Friday, April 01, 2011 7:36 AM
> Subject: Re: [R-390] Orange Drop vs ceramic disc
>
>>> Those are metallized film capacitors, which for the reasons
>>> previously discussed (breakdown/self healing) are disasters waiting
>>> to happen in boatanchors.  I'm not aware of any axial lead
>>> film-and-foil caps currently available.  Much better to use the best
>>> part for the job (film-and-foil) and accept a bit of inconvenience
>>> installing them than to use a lesser part just for convenience.
>> I wish I had known.  I recapped an R390A with these:
>>
>> http://www.justradios.com/capacitors.html
>>
>> Barry - N4BUQ



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