If it looks like a light bulb, the "PZ" is most likely a ballast. If it looks similar in construction to the 47, it may have been a 47 marked for proprietary reasons by some company to keep people buying their tubes.
I would check the tubes, chances are good that one, or both of the 47's need replacing as well as the 80.
The large envelope on those tubes served 2 purposes 1) room for the internals. 2) heat dissipation.
Based on your desription, the radio is likely 1929 to 1931 for year of manufacture. Unless the chassis or radio tag specifically states "TRF", you may have a heterodyne reciever. This may help with some of the references you may have.
I would also watch the 47's as the radio warms up. If one of the filter caps is going bad (often the one across the field coil winding), the 47's will start to develop a purple glow. Shut the radio off right away, and check the filter capacitor block for one that is begining to short out.
: Can anyone identify the model number of a Gilfillan TRF (4 section tuning cap on single shaft) smallish lowboy, 3 knob console, carved oak. It has 8 tubes.80, 47, PZ ("Pentode" stamped on socket), 35, 35, 35, 35, 27. What is a PZ? Audio Preamp? It seems to be hooked to the tone control. The 80, 47 & PZ are very large.
: Serial Number? 32946 stamped in big letters on chassis.
: I Just bought it from a lady that bought it in '51 from an antique dealer. It only sorta works & I need a schematic.
: Thanks, Ron...
: Hi,
: What does the internal portion of the "PZ" look like? Like the 47? Or a lightbulb?
: If it looks like a light bulb, the "PZ" is most likely a ballast. If it looks similar in construction to the 47, it may have been a 47 marked for proprietary reasons by some company to keep people buying their tubes.
: I would check the tubes, chances are good that one, or both of the 47's need replacing as well as the 80.
: The large envelope on those tubes served 2 purposes 1) room for the internals. 2) heat dissipation.
: Based on your desription, the radio is likely 1929 to 1931 for year of manufacture. Unless the chassis or radio tag specifically states "TRF", you may have a heterodyne reciever. This may help with some of the references you may have.
: I would also watch the 47's as the radio warms up. If one of the filter caps is going bad (often the one across the field coil winding), the 47's will start to develop a purple glow. Shut the radio off right away, and check the filter capacitor block for one that is begining to short out.
: : Can anyone identify the model number of a Gilfillan TRF (4 section tuning cap on single shaft) smallish lowboy, 3 knob console, carved oak. It has 8 tubes.80, 47, PZ ("Pentode" stamped on socket), 35, 35, 35, 35, 27. What is a PZ? Audio Preamp? It seems to be hooked to the tone control. The 80, 47 & PZ are very large.
: : Serial Number? 32946 stamped in big letters on chassis.
: : I Just bought it from a lady that bought it in '51 from an antique dealer. It only sorta works & I need a schematic.
: : Thanks, Ron...
What Riders has listed, has a gap in coverage of a few years. At this point, unless Norm can identify it from the tube line-up; I do not have as many references as he does; you might do well to try to identify it from various guides. I know there are a couple specific to consoles, this may be the only way to identify it. Finding a schematic will likely be difficult, even if it is identified, due to that gap in coverage in Riders.
This is one you may have to work out intuitively.
: I checked the (blue Arcturus) PZ as a 47 & it tests about the same transconductance as the 47 at ~1500 (Hickok). It does have the 2 little springs at the top of the plate. I am pretty sure this is a TRF because the 4 capacitor sections are all the same size. I can't read the tag as it is 80+% worn off. I still need a model number.
: Thanks again, Ron...
: : Hi,
: : What does the internal portion of the "PZ" look like? Like the 47? Or a lightbulb?
: : If it looks like a light bulb, the "PZ" is most likely a ballast. If it looks similar in construction to the 47, it may have been a 47 marked for proprietary reasons by some company to keep people buying their tubes.
: : I would check the tubes, chances are good that one, or both of the 47's need replacing as well as the 80.
: : The large envelope on those tubes served 2 purposes 1) room for the internals. 2) heat dissipation.
: : Based on your desription, the radio is likely 1929 to 1931 for year of manufacture. Unless the chassis or radio tag specifically states "TRF", you may have a heterodyne reciever. This may help with some of the references you may have.
: : I would also watch the 47's as the radio warms up. If one of the filter caps is going bad (often the one across the field coil winding), the 47's will start to develop a purple glow. Shut the radio off right away, and check the filter capacitor block for one that is begining to short out.
: : : Can anyone identify the model number of a Gilfillan TRF (4 section tuning cap on single shaft) smallish lowboy, 3 knob console, carved oak. It has 8 tubes.80, 47, PZ ("Pentode" stamped on socket), 35, 35, 35, 35, 27. What is a PZ? Audio Preamp? It seems to be hooked to the tone control. The 80, 47 & PZ are very large.
: : : Serial Number? 32946 stamped in big letters on chassis.
: : : I Just bought it from a lady that bought it in '51 from an antique dealer. It only sorta works & I need a schematic.
: : : Thanks, Ron...
I also checked Rider and Mallory Encyclopedia which lists tubes for different models. I didn't locate any similar Gilfillan models. Gilfillan made radios for other companies. Is there any other names or numbers on your radio?
Norm
: Hi,
: Many of the first heterodynes and super heterodynes had 4 tuning caps all the same size.
: What Riders has listed, has a gap in coverage of a few years. At this point, unless Norm can identify it from the tube line-up; I do not have as many references as he does; you might do well to try to identify it from various guides. I know there are a couple specific to consoles, this may be the only way to identify it. Finding a schematic will likely be difficult, even if it is identified, due to that gap in coverage in Riders.
: This is one you may have to work out intuitively.
: : I checked the (blue Arcturus) PZ as a 47 & it tests about the same transconductance as the 47 at ~1500 (Hickok). It does have the 2 little springs at the top of the plate. I am pretty sure this is a TRF because the 4 capacitor sections are all the same size. I can't read the tag as it is 80+% worn off. I still need a model number.
: : Thanks again, Ron...
: : : Hi,
: : : What does the internal portion of the "PZ" look like? Like the 47? Or a lightbulb?
: : : If it looks like a light bulb, the "PZ" is most likely a ballast. If it looks similar in construction to the 47, it may have been a 47 marked for proprietary reasons by some company to keep people buying their tubes.
: : : I would check the tubes, chances are good that one, or both of the 47's need replacing as well as the 80.
: : : The large envelope on those tubes served 2 purposes 1) room for the internals. 2) heat dissipation.
: : : Based on your desription, the radio is likely 1929 to 1931 for year of manufacture. Unless the chassis or radio tag specifically states "TRF", you may have a heterodyne reciever. This may help with some of the references you may have.
: : : I would also watch the 47's as the radio warms up. If one of the filter caps is going bad (often the one across the field coil winding), the 47's will start to develop a purple glow. Shut the radio off right away, and check the filter capacitor block for one that is begining to short out.
:
: : : : Can anyone identify the model number of a Gilfillan TRF (4 section tuning cap on single shaft) smallish lowboy, 3 knob console, carved oak. It has 8 tubes.80, 47, PZ ("Pentode" stamped on socket), 35, 35, 35, 35, 27. What is a PZ? Audio Preamp? It seems to be hooked to the tone control. The 80, 47 & PZ are very large.
: : : : Serial Number? 32946 stamped in big letters on chassis.
: : : : I Just bought it from a lady that bought it in '51 from an antique dealer. It only sorta works & I need a schematic.
: : : : Thanks, Ron...
: Hi
: I also checked Rider and Mallory Encyclopedia which lists tubes for different models. I didn't locate any similar Gilfillan models. Gilfillan made radios for other companies. Is there any other names or numbers on your radio?
: Norm
: : Hi,
: : Many of the first heterodynes and super heterodynes had 4 tuning caps all the same size.
: : What Riders has listed, has a gap in coverage of a few years. At this point, unless Norm can identify it from the tube line-up; I do not have as many references as he does; you might do well to try to identify it from various guides. I know there are a couple specific to consoles, this may be the only way to identify it. Finding a schematic will likely be difficult, even if it is identified, due to that gap in coverage in Riders.
: : This is one you may have to work out intuitively.
:
: : : I checked the (blue Arcturus) PZ as a 47 & it tests about the same transconductance as the 47 at ~1500 (Hickok). It does have the 2 little springs at the top of the plate. I am pretty sure this is a TRF because the 4 capacitor sections are all the same size. I can't read the tag as it is 80+% worn off. I still need a model number.
: : : Thanks again, Ron...
: : : : Hi,
: : : : What does the internal portion of the "PZ" look like? Like the 47? Or a lightbulb?
: : : : If it looks like a light bulb, the "PZ" is most likely a ballast. If it looks similar in construction to the 47, it may have been a 47 marked for proprietary reasons by some company to keep people buying their tubes.
: : : : I would check the tubes, chances are good that one, or both of the 47's need replacing as well as the 80.
: : : : The large envelope on those tubes served 2 purposes 1) room for the internals. 2) heat dissipation.
: : : : Based on your desription, the radio is likely 1929 to 1931 for year of manufacture. Unless the chassis or radio tag specifically states "TRF", you may have a heterodyne reciever. This may help with some of the references you may have.
: : : : I would also watch the 47's as the radio warms up. If one of the filter caps is going bad (often the one across the field coil winding), the 47's will start to develop a purple glow. Shut the radio off right away, and check the filter capacitor block for one that is begining to short out.
: :
: : : : : Can anyone identify the model number of a Gilfillan TRF (4 section tuning cap on single shaft) smallish lowboy, 3 knob console, carved oak. It has 8 tubes.80, 47, PZ ("Pentode" stamped on socket), 35, 35, 35, 35, 27. What is a PZ? Audio Preamp? It seems to be hooked to the tone control. The 80, 47 & PZ are very large.
: : : : : Serial Number? 32946 stamped in big letters on chassis.
: : : : : I Just bought it from a lady that bought it in '51 from an antique dealer. It only sorta works & I need a schematic.
: : : : : Thanks, Ron...
Your radio uses push-pull output with 47 and PZ tubes. It should still operate with one or the other tubes removed.
You may want to contact Floyd Paul. He is an expert on Los Angeles made radios and wrote a book on the subject. Your radio should have been made in Los Angeles. Send me an email if you want his address.
Norm
: Hello again:
: This is definately a Gilfillan as the escutchon has the GB logo & says Gilfillan and Gilfillan Bros. No other names to work with.
: You are right that it IS a Superhet. It helps to know that a bunch. I see two large square cans that turn out to be 175 KHz IF's (I sweapt a generator around the low freqs & hear the tone at that freq & amplitude gets much better as I work forward to the first IF tube. The 27 must be the LO. I was having trouble getting it to keep running so I tried a different tube (also a Arcturus 27)with almost the same transconductance & it is working very well now. It is very sensitive with just a short clip lead on the antenna. Lots of stations & noise. Only a couple (or four) problems now are: 1. the big variable antenna resistor to control volume does not do anything now, just max sensitivity only. It was working. 2.: the PZ (47) tube does nothing, in there or pulled out! Audio is not real strong & is a sorta distorted, (in spite of the lack of a volume control as in 1.) 3.: There are oscillations kinda like a bfo on all stations, which I can remove by loading an if tube with my oscilloscope probe. (Tube shields are all there) soooo... 4. A cracked tuning gear jams the tuning (grind, clamp/glue should fix it).
: Still some guessing to do. A model number/schematic would sure still be nice to have.
: Many thanks for your help on searching for the model & schematic.. This is a very cool radio & I'll stay with it.
: Ron...
: : Hi
: : I also checked Rider and Mallory Encyclopedia which lists tubes for different models. I didn't locate any similar Gilfillan models. Gilfillan made radios for other companies. Is there any other names or numbers on your radio?
: : Norm
: : : Hi,
: : : Many of the first heterodynes and super heterodynes had 4 tuning caps all the same size.
: : : What Riders has listed, has a gap in coverage of a few years. At this point, unless Norm can identify it from the tube line-up; I do not have as many references as he does; you might do well to try to identify it from various guides. I know there are a couple specific to consoles, this may be the only way to identify it. Finding a schematic will likely be difficult, even if it is identified, due to that gap in coverage in Riders.
: : : This is one you may have to work out intuitively.
: :
: : : : I checked the (blue Arcturus) PZ as a 47 & it tests about the same transconductance as the 47 at ~1500 (Hickok). It does have the 2 little springs at the top of the plate. I am pretty sure this is a TRF because the 4 capacitor sections are all the same size. I can't read the tag as it is 80+% worn off. I still need a model number.
: : : : Thanks again, Ron...
: : : : : Hi,
: : : : : What does the internal portion of the "PZ" look like? Like the 47? Or a lightbulb?
: : : : : If it looks like a light bulb, the "PZ" is most likely a ballast. If it looks similar in construction to the 47, it may have been a 47 marked for proprietary reasons by some company to keep people buying their tubes.
: : : : : I would check the tubes, chances are good that one, or both of the 47's need replacing as well as the 80.
: : : : : The large envelope on those tubes served 2 purposes 1) room for the internals. 2) heat dissipation.
: : : : : Based on your desription, the radio is likely 1929 to 1931 for year of manufacture. Unless the chassis or radio tag specifically states "TRF", you may have a heterodyne reciever. This may help with some of the references you may have.
: : : : : I would also watch the 47's as the radio warms up. If one of the filter caps is going bad (often the one across the field coil winding), the 47's will start to develop a purple glow. Shut the radio off right away, and check the filter capacitor block for one that is begining to short out.
: : :
: : : : : : Can anyone identify the model number of a Gilfillan TRF (4 section tuning cap on single shaft) smallish lowboy, 3 knob console, carved oak. It has 8 tubes.80, 47, PZ ("Pentode" stamped on socket), 35, 35, 35, 35, 27. What is a PZ? Audio Preamp? It seems to be hooked to the tone control. The 80, 47 & PZ are very large.
: : : : : : Serial Number? 32946 stamped in big letters on chassis.
: : : : : : I Just bought it from a lady that bought it in '51 from an antique dealer. It only sorta works & I need a schematic.
: : : : : : Thanks, Ron...
Just one thing to add - PZ is an Arcturus replacement for 47. It should be blue and have two small coil springs above the filament. Other than that it will look like a 47.
Norm
: Can anyone identify the model number of a Gilfillan TRF (4 section tuning cap on single shaft) smallish lowboy, 3 knob console, carved oak. It has 8 tubes.80, 47, PZ ("Pentode" stamped on socket), 35, 35, 35, 35, 27. What is a PZ? Audio Preamp? It seems to be hooked to the tone control. The 80, 47 & PZ are very large.
: Serial Number? 32946 stamped in big letters on chassis.
: I Just bought it from a lady that bought it in '51 from an antique dealer. It only sorta works & I need a schematic.
: Thanks, Ron...