I am righ in the middle of replacing the electrolytics and wish to place the capacitors inside the old cardboard Solar 119-47B type ED cap. I prefer to keep the original look as much as possible. It has three wires and I was initally assuming one was a common negative for both internal caps. However, before I get carried away I want to understand the circuit a little better. I can tell from the parts list that C8 and C10 are the values I need. 5mF and 5mF and at least 200 and 250V (I have two at 4.7mF @ 250V)
Okay, so now I am looking at the schematic at C8 and C10 shown near the Field coil and trying to determine the best way to configure the two capacitors that I wish to blend into one authentic looking assembly. I have at hand two electrolytics and was about to connect them together at the negative side as I typically do when working on can capacitors. However, this old paper wrapped electrolytic cap has no indication as to the value versus connection point.
This schematic shows -3.5V on one side of the C10 (between R7 and R8). It also appears to have the C8 connected to one side of the field coil and the other to the opposite (+?)side of C10.
Just as a reference: The capacitor physically connected as follows.
1. A dark green/black connects to the tap on the wirewound resistor block at at the R7 R8 interface.
2. A red wire connects to Pin 8 of the 5Y3.
3. A yellow wire connects via a small rerminal lug to the power transformer, pin 8 of the 6K6 and to the Speaker coil.
These connections are orignal and verified on another identical set.
I remembered reading something about negative filtered poswer supplies here on Nostalgia Air under the training section:
http://www.nostalgiaair.org/References/Articles/TheFlash/Flash02.htm
So, after all that I think my question is: on C8, which is the negative side? Is it the side connected nearest the field coil? or nearest C10? I have to believe that C10 negative is connected to R10, and between R7 & R8.
I don't want to cause a short or any of the related sparks, smoke or damage as intimated in the referenced article.
Kindest Regards
JW
I did an Airline 62-282, the farm radio version. It was a lot of fun.
See my comments below. These should verify your suspicions.
1. A dark green/black connects to the tap on the wirewound resistor block at at the R7 R8 interface. This is the negative of C10.
2. A red wire connects to Pin 8 of the 5Y3G. This is the positive common for C8 and C10.
3. A yellow wire connects via a small terminal lug to the power transformer, pin 8 of the 6K6G and to the Speaker coil. This is the negative of C8.
We are used to common negatives, but this is different. This arrangement allows the creation of a negative voltage capable of biasing the 6K6G.
Best Regards,
Bill Grimm
That is exactly what I was looking for! Thanks a million for the help.
That dial indicator ribbon arrangement on this model is very unique and delicate. The preset mechanisms were frozen up on this one.
I do have a third unit that is a 6 volt farm version to restore as well. I am curious as to what you used for a power supply?
Jeff W
:Hi JW,
:
: I did an Airline 62-282, the farm radio version. It was a lot of fun.
: See my comments below. These should verify your suspicions.
:
:1. A dark green/black connects to the tap on the wirewound resistor block at at the R7 R8 interface. This is the negative of C10.
:2. A red wire connects to Pin 8 of the 5Y3G. This is the positive common for C8 and C10.
:3. A yellow wire connects via a small terminal lug to the power transformer, pin 8 of the 6K6G and to the Speaker coil. This is the negative of C8.
:
: We are used to common negatives, but this is different. This arrangement allows the creation of a negative voltage capable of biasing the 6K6G.
:
:Best Regards,
:
:Bill Grimm
:
:
::Hello Bill G,
::
::That is exactly what I was looking for! Thanks a million for the help.
::
::That dial indicator ribbon arrangement on this model is very unique and delicate. The preset mechanisms were frozen up on this one.
::
::I do have a third unit that is a 6 volt farm version to restore as well. I am curious as to what you used for a power supply?
::
::Jeff W
::
:::Hi JW,
:::
::: I did an Airline 62-282, the farm radio version. It was a lot of fun.
::: See my comments below. These should verify your suspicions.
:::
:::1. A dark green/black connects to the tap on the wirewound resistor block at at the R7 R8 interface. This is the negative of C10.
:::2. A red wire connects to Pin 8 of the 5Y3G. This is the positive common for C8 and C10.
:::3. A yellow wire connects via a small terminal lug to the power transformer, pin 8 of the 6K6G and to the Speaker coil. This is the negative of C8.
:::
::: We are used to common negatives, but this is different. This arrangement allows the creation of a negative voltage capable of biasing the 6K6G.
:::
:::Best Regards,
:::
:::Bill Grimm
:::
:::
::
:
When restoring the farm radio you will likely find the vibrator to be defective. If so don't google 'vibrator'. I still get junk email from people who think I am a sex starved, over weight, middleaged woman.
Best regards,
Bill Grimm
Thank you for all the useful information!!
I havent,t tested the tubes in the farm radio yet. However if I find the vibrator tube bad, I will definately avoid any chance of mistaken identity or product required. Ha, ha, ha! Fuuunnnny!
I will have to use a few ,-personal,-etc,-etc. in my search and disable all cookies just in case. However, I use Bing(livesearch)and cashback so I hope to get a rebate on "whatever" it is that I end up buying.:-)
Jeff
Jeff
:Hi Jeff,
: I built my own power supply. It is necessary to provide enough current to power the radio. Most wall mounted supplies can't do it. The radio is going ot draw about an ampere when running.
: The power supply had a bridge rectifier and a capacitor. I think it was on the order of 100 uf 15 volt.
: The main thing was I used battery terminals for the 6 volt output. These are available at auto parts stores. This allows the radio to connect to the power supply using its original battery clips, keeping the radio as original as possible.
: The power supply was mounted in an enclosed box with a battery terminal on each side, like ears. This minimized the possibility of the radio's battery clips shorting.
:
: When restoring the farm radio you will likely find the vibrator to be defective. If so don't google 'vibrator'. I still get junk email from people who think I am a sex starved, over weight, middleaged woman.
:
:Best regards,
:
:Bill Grimm
: