I recapped the first one and it hums but doesn't pickup any stations. I have a 4 foot antenna connected to it. The tag showing the model number is half gone. It shows a model number of 4. I think it’s a model 442. The chassis number is was there, RE-91. I have started checking the resistors and found it has a flexible resistor from pin 4 of the 50L6 to pin 8 of the 35Z5. The resistor measures about 1900 ohms. However this does not match the cloth color code. The "A" color looks more like a light tan and the "B" color is black. I looked at two schematics on the site but neither appears to completely match this radio. I think its resistor R-242 with a value of 2000 ohms. I tried comparing it to the second Arvin. However the tag showing the model number lists the same tubes, but the chassis has the miniature tubes and is completely different. Sadly when they cut the power cord they also cut the oscillator coil in this radio. Any help would be appreciated.
Best to recheck all your work to be sure that you didn't make a wiring error, which is very easy to do. Next, check all the voltages at the tube bins and check coils for continuity.
Doug
:Recently purchased two little Arvin radios.
:I recapped the first one and it hums but doesn't pickup any stations. I have a 4 foot antenna connected to it. The tag showing the model number is half gone. It shows a model number of 4. I think it’s a model 442. The chassis number is was there, RE-91. I have started checking the resistors and found it has a flexible resistor from pin 4 of the 50L6 to pin 8 of the 35Z5. The resistor measures about 1900 ohms. However this does not match the cloth color code. The "A" color looks more like a light tan and the "B" color is black. I looked at two schematics on the site but neither appears to completely match this radio. I think its resistor R-242 with a value of 2000 ohms. I tried comparing it to the second Arvin. However the tag showing the model number lists the same tubes, but the chassis has the miniature tubes and is completely different. Sadly when they cut the power cord they also cut the oscillator coil in this radio. Any help would be appreciated.
:
In looking at probably a close enough schematic of you set to work with, as is referenced below, that set is probably incorporating two of the~ 1 watt ''grub worm '' flexible power resistors. One is located off pin # 7 of the 35Z5 going up to the 12SA7 in the series filamental string , to make up for the dedicated I.F. tube not being incorporated on your set. Schematic markup reference:
Their color coding may be intact with one color being placed on one crimped end connector and the others being on the center '' fabric '' area of the units. With time, gradually heat-fading, that units Red-Red-Red color codings of red will now assuredly have made its initial transition to a shade of brown and then yet another eventual transition to black.
That one 2.2K resistor which you are mentioning of interest, is the B+ filtering / dropping resistor that takes the raw B+ and drops it down to the sub B+ level to feed the screen grid of the AF out tube, the 12SA7 mixer tube …via the sets sole I.F. transformer, and a line that is further dropped in level to fed the plate of the 6SQ7 1st audio stage.
Lastly…..looking inside the rear up at the antenna coil mounted just to the left of the speaker… is the hank of double cotton covered antenna wire still intact at its full length or has some '' shyster '' made off with it and left you but a mere short stub of wire ?... lol..
73's de Edd
I probably confused the problem talking about two radios in the same posting.
The Arvin Model 422 I have is very similar to
http://www.nostalgiaair.org/PagesByModel/514/M0012514.pdf
It hums but doesn't pickup any stations.
It only has one flexible resistor R242 from pin 4 of the 50L6 to pin 8 of the 35Z5. It reads OK but is very brittle and the wires are exposed. I plan to replace it will a 2k, 1watt. Should it be replaced with a wire wound or carbon? I traced most of the wiring and found no errors. There is a connection from the 2k flexible resistor to the IF. I found that resistor R171, 15M is open. The antenna coil shows continuity, but the antenna wire is only 4 feet long. How long should the wire be to receive any stations?
I appreciate all your help.
:
:In looking at probably a close enough schematic of you set to work with, as is referenced below, that set is probably incorporating two of the~ 1 watt ''grub worm '' flexible power resistors. One is located off pin # 7 of the 35Z5 going up to the 12SA7 in the series filamental string , to make up for the dedicated I.F. tube not being incorporated on your set.
:
:
:Their color coding may be intact with one color being placed on one crimped end connector and the others being on the center '' fabric '' area of the units. With time, gradually heat-fading, that units Red-Red-Red color codings of red will now assuredly have made its initial transition to a shade of brown and then yet another eventual transition to black.
:
:
:That one 2.2K resistor which you are mentioning of interest, is the B+ filtering / dropping resistor that takes the raw B+ and drops it down to the sub B+ level to feed the screen grid of the AF out tube, the 12SA7 mixer tube …via the sets sole I.F. transformer, and a line that is further dropped in level to fed the plate of the 6SQ7 1st audio stage.
:
:
:
:Lastly…..looking inside the rear up at the antenna coil mounted just to the left of the speaker… is the hank of double cotton covered antenna wire still intact at its full length or has some '' shyster '' made off with it and left you but a mere short stub of wire ?... lol..
:
:
:
:Schematic markup reference:
:
:
:
:
:
:73's de Edd
:
:
:
:
:
:
:
:
: