new guy again,, 44 chassis
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City: Phoenixville PA
Just wanted to bounce this off you guys before I get to deep in this unit.
I recapped and also retubed this set. Now I get no stations, I have a pretty long wirer, like 20' hooked to the antenna to the ground.
The volume can be adjusted very loud but no stations just static. I did get a small small low spanish voice at one point but thats it.
Any thoughts?
thanks all great site.
Rich
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Hi Rich,
Did it get stations prior to the full recap? My general assumption on sets that look reasonably intact is that it probably more or less worked when it was last used. After replacing the just electrolytics I usually bring up a set on a variac and see if it's working. If it is that's a good baseline to start from before making my way through the rest of the recap.
Have you done an alignment or checked things out with a signal generator?
It might be useful to also check coil continuity (unless it was working prior to the recap).
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thanks for the response, it never worked had lots of bad parts, I need to put a scope on it.
I didnt replace the box caps,, Lots of them are listed as .05uf and .25uf
I want to replace these as well not sure what voltage I should use?
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Oh - well that's not too bad then. It sounds like it kind of works with just electrolytics replaced.
For paper caps I just replace with the common 630V film caps:
http://www.radiodaze.com/film/
Actually for restuffing blocks I like to use these since they're a bit smaller than the above and cost less (the above are obviously better for restuffing tubular caps):
http://www.capacitorworld.net/product/me...apacitors/
My advice would be to work your way through the restuffing of the blocks in sections, restuffing no more than 2-3 blocks at a time. After restuffing each section check that the radio is still more or less working. If not, double-check wiring.
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Make sure you check all the RF coils. This is often the reason of the lack of reception.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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(04-27-2018, 10:41 AM)safeshow Wrote: I have a pretty long wirer, like 20' hooked to the antenna to the ground.
I suspect this is just a mistake in keyboarding but you do not want the antenna and the ground connected together.
For those bakelite block capacitors here's a nice how to thread: http://www.philcoradio.com/phorum/showth...p?tid=9107
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the 2 connections on the back of the chassis 1 states antenna the other gnd . I assumed the antenna wire would loop to both I will see, Otherwise what is the gnd connector for?
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I found a coil that measured 33 and should be 27 ohm, and a resistor 1.4k should be 1000ohm not sure if the coil is in spec.
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For the coil -it's fine.
The resistor is out of spec and should be replaced.
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You can leave the connection labeled "ground" unconnected to anything. Sometimes folks will connect it to a cold water pipe if you still have copper pipe, or to an earth ground rod, or to the ground in their electrical system. This ensures the chassis is at ground potential and can sometimes help reduce unwanted electrical noise.
The connection labeled "antenna" is where you connect that 20 foot wire. You do not connect the antenna and ground together.
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thanks I ordered several resistors, the coils seem ok, And the .05 caps seem ok measure .068,, and the .25 also seem ok a bit off both close not open or shorted,,, I will get the resistors an see what happens,
I ordered several 5watt an 3 watt resistors, the old ones are big not 100% sure what wattage
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The original caps might measure OK with a capacitance meter (although in my experience this is rare). The larger concern is their leakage at operating voltage.
Most modern multimeter style capacitor testers do not do this. I have a Sencore meter than is able to test for leakage near the rated voltage. I got it mostly it out of curiosity - and I've found that almost without exception the paper caps I've measure in these old sets are very leaky and unreliable. Mica caps are usually still in good shape (note that on occasion you might find bakelite blocks that contain mica caps - these are typically ~120pF - but just as often paper caps were used for the same value).
If you want the radio to work as it was originally you will want to replace all of the capacitors. The original capacitors are many many decades past their intended lifetimes.
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where do you get these values? It dosnt look like Mouser has them and I did see them on Radio days.
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For those following along here's the 44 schematic link: http://www.nostalgiaair.org/pagesbymodel...013581.pdf
Capacitance measurements on those old paper caps may look OK but unless you test them at higher voltages the leakage current may be unacceptable. Folks generally just change all of them out rather than wait for them to fail. Restuffing those black bakelite block capacitors is not really that difficult. Most of the resistors are probably 1/2 watt although some can be larger wattage.
Here's a link to a pdf for the 44 Instructions (thanks to Jeremy Schotter): https://www.dropbox.com/s/qlhk6u12ap0kcv...s.PDF?dl=0
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Modern component values are somewhat different than the pre-WW II versions. Just get the version closest to what it's supposed to be. Most of the components are pretty forgiving in terms of tolerance (say +/- 20%).
For .05uF you can replace with .047uF:
http://www.radiodaze.com/axial-film-047mf-630v/
For .25uF you can replace with .22uF:
http://www.radiodaze.com/axial-film-22mf-630v/
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