Rescued an 87 lowboy today.
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I've walked past this radio several times the past few years. It was sitting in a musty back room with several other old radios that need help, but aren't getting it and since I already have an 87 high boy, I really didn't think of this radio until today when I looked at it again. It had no mounting bolts for the chassis or speaker the grill or grill cloth was missing and it had no knobs until I found the dial knob laying on the floor. Also, the 45s and two 26s were gone off the chassis, but I saw the beginnings of complete 87 lowboy and made an offer on the set. So, it is now at my place awaiting further repair and parts. I had the other two knobs and a good pair of 45s, so that is a start.
No matter where you go, there you are.
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Hey Jayce
The 87 is a good old set! I think Philco called it their Neutrodyne Plus. Can't remember what the Plus was.
Here's what I did on mine about two years ago. Best I remember I started on Sunday after Church and had it working by 11pm.
http://philcoradio.com/phorum/showthread.php?tid=3490
Rebuilt the filter bank, replaced three or four bypass caps, rewound a couple of the RF coils, replaced some weak 26's, and did the alignment. Play great everyday for about a year then the input cap in the bank shorted. I should have used a mylar but I chose to use some cheap electrolytic jobs. It's been out in the shed for while now.
Terry
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Mylar/poly film caps are definitely what you want to use in an early AC set that formerly used paper capacitors as filters, small value electrolytics tend to dry up faster then larger value ones it seems. Also they are not easy to change in these sets unless you mount them on a separate terminal strip. I know that some guys claim that the old paper filters don't need to be changed, well maybe that was true in 1963, or 1973, but this is 80+ years later, they can and will fail at some point.
Regards
Arran
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As Arran said, you really do want to use film type caps for the filters in these sets. Because of their low capacitance value they are subjected to very high ripple voltages, especially the first cap after the rectifier.
Modern small value electrolytics are not designed for this type of service and will fail in a short time due to the excessive ripple current and resulting overheating.
I do have a few early AK sets with their original paper filter banks, but they are only played occasionally and at reduced line voltage. If you will be using the radio on a regular basis, then the filter replacement is definitely warranted.
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I noticed that I have a 2mf mylar in my parts bin, I should drop it in. When it quit the volume dropped and I remember looking into the back of the set and the 80 tube had an ANGRY RED GLOW. I quick turned it off knowing what the problem was.
Terry
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There is also the fact that larger value mylar/polyester film caps like 1 to 4 uf at 630 volts are really not that expensive, more expensive then an equivalent electrolytic but still cheaper then the average replacement type #80 tube.
In the older AC sets it's the field coil and filter chokes in the power supply that take out most of the ripple, at the time there were no high value filter capacitors available at a reasonable cost so they used inductive reactance for filtering rather then capacitance. After Mr. Mershon came out with his wet electrolytic capacitors it became easier and less expensive to use large value capacitors to filter out ripple rather then inductors.
Regards
Arran
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Got to do a little tinkering on the 87 tonight at my friend's place and have some good news. We got a bit of life out of the radio and have good signs that all of the 'heavy iron' as he calls the transformers and such are ok. I actually found a faint date written on the speaker cone of 6-18-29. That is cool, but now that probably means I will have to try and find one of the intricate grill inserts to complete this radio.
No matter where you go, there you are.
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I wonder if the set was actually manufactured in June 1929 or if the speaker was manufactured ahead of time? Early versions have the fretwork grille, later versions have a tapestry cloth in the same hole.
Regards
Arran
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I did an 87H for my daughter awhile back and was surprised at just how good the set sounded/received.
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I checked the cabinet for any clues as to when it might have been made. No dates, but I did find a stamp made into the wood claiming it was made at Philco Furniture, Plant 2. Not sure if that helps, but it is neat. With things already underway on this radio, I definitely need to locate a grill. I can see something was attatched behnd the main opening with wood screws and I can make out a faint square outline in the wood from where it was at.
No matter where you go, there you are.
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The 87 is back together and working again. It was a bit weak in my home until I did some swapping of the 26 tubes between it and a couple other radios I don't use often, but it might still need a tweak or two. Biggest issue is I still lack a working tube tester and will be putting the possible repair of mine front and center soon. Sadly, it never did seem to like type 26 tubes. A big thanks to Chuck as the packet I received came in time to help out with both the lowboy and my highboy. Now, to find a proper grill insert for it.
No matter where you go, there you are.
(This post was last modified: 11-11-2013, 11:08 PM by Jayce.)
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