I am still working on the Hallicrafters S-77A I rescued from the scrap yard a while back, and I have this question: I have an S-77A, while I am working from a schematic for an S-77. Does anyone know the exact difference between the two? All I can find out is the "A" is slightly different. What is the difference? Thanks,
Lewis

Lewis,

I have the service information from Radio College of Canada for the S-77A. I'll try to get it posted for you to download tomorrow.

Richard

:I am still working on the Hallicrafters S-77A I rescued from the scrap yard a while back, and I have this question: I have an S-77A, while I am working from a schematic for an S-77. Does anyone know the exact difference between the two? All I can find out is the "A" is slightly different. What is the difference? Thanks,
:Lewis

In Chuck Dachis' book, 'Radios by Hallicrafters', it states that the S-77 was produced in '50-'51 and The S-77A was produced from '52-'55.
Both listed new at $89.95.
It goes on to say: 'The specifications, functions and appearance of the S-77A are the same as the S-77. (I) see no differences, with the possible exception of minor value changes in some components'.
It would be interesting to know what circuit(s) specifically they were upgrading.

:Lewis,
:
:I have the service information from Radio College of Canada for the S-77A. I'll try to get it posted for you to download tomorrow.
:
:Richard
:
::I am still working on the Hallicrafters S-77A I rescued from the scrap yard a while back, and I have this question: I have an S-77A, while I am working from a schematic for an S-77. Does anyone know the exact difference between the two? All I can find out is the "A" is slightly different. What is the difference? Thanks,
::Lewis
:
:

:In Chuck Dachis' book, 'Radios by Hallicrafters', it states that the S-77 was produced in '50-'51 and The S-77A was produced from '52-'55.
: Both listed new at $89.95.
: It goes on to say: 'The specifications, functions and appearance of the S-77A are the same as the S-77. (I) see no differences, with the possible exception of minor value changes in some components'.
: It would be interesting to know what circuit(s) specifically they were upgrading.
:
::Lewis,
::
::I have the service information from Radio College of Canada for the S-77A. I'll try to get it posted for you to download tomorrow.
::
::Richard
::
:::I am still working on the Hallicrafters S-77A I rescued from the scrap yard a while back, and I have this question: I have an S-77A, while I am working from a schematic for an S-77. Does anyone know the exact difference between the two? All I can find out is the "A" is slightly different. What is the difference? Thanks,
:::Lewis
::
::
:
Tnx, guys, I'll say this about the beast. With a RF amp and two IF amps, this thing, connected to about 75 feet of longwire antenna will pick up Radio Pluto, if the Plutonomiums have a HF transmitter on the air.
Lewis

It does look a lot like an S-40B, only with an AC/DC power supply. In good tune, these are very sensitive receivers.

::In Chuck Dachis' book, 'Radios by Hallicrafters', it states that the S-77 was produced in '50-'51 and The S-77A was produced from '52-'55.
:: Both listed new at $89.95.
:: It goes on to say: 'The specifications, functions and appearance of the S-77A are the same as the S-77. (I) see no differences, with the possible exception of minor value changes in some components'.
:: It would be interesting to know what circuit(s) specifically they were upgrading.
::
:::Lewis,
:::
:::I have the service information from Radio College of Canada for the S-77A. I'll try to get it posted for you to download tomorrow.
:::
:::Richard
:::
::::I am still working on the Hallicrafters S-77A I rescued from the scrap yard a while back, and I have this question: I have an S-77A, while I am working from a schematic for an S-77. Does anyone know the exact difference between the two? All I can find out is the "A" is slightly different. What is the difference? Thanks,
::::Lewis
:::
:::
::
:
:
:
:
:
:
:Tnx, guys, I'll say this about the beast. With a RF amp and two IF amps, this thing, connected to about 75 feet of longwire antenna will pick up Radio Pluto, if the Plutonomiums have a HF transmitter on the air.
:Lewis
:

: It does look a lot like an S-40B, only with an AC/DC power supply. In good tune, these are very sensitive receivers.

I wish it were a S-40 or something with a power transformer. I just don't completely trust an AC/DC radio. I think i will go down to my friendly Home Depot and buy an in-wall GFCI and put my whole shop on it. Or, what the heck, get a GFCI circuit breaker and put the whole circuit on it from the breaker box.
Lewis

:
:
:::In Chuck Dachis' book, 'Radios by Hallicrafters', it states that the S-77 was produced in '50-'51 and The S-77A was produced from '52-'55.
::: Both listed new at $89.95.
::: It goes on to say: 'The specifications, functions and appearance of the S-77A are the same as the S-77. (I) see no differences, with the possible exception of minor value changes in some components'.
::: It would be interesting to know what circuit(s) specifically they were upgrading.
:::
::::Lewis,
::::
::::I have the service information from Radio College of Canada for the S-77A. I'll try to get it posted for you to download tomorrow.
::::
::::Richard
::::
:::::I am still working on the Hallicrafters S-77A I rescued from the scrap yard a while back, and I have this question: I have an S-77A, while I am working from a schematic for an S-77. Does anyone know the exact difference between the two? All I can find out is the "A" is slightly different. What is the difference? Thanks,
:::::Lewis
::::
::::
:::
::
::
::
::
::
::
::Tnx, guys, I'll say this about the beast. With a RF amp and two IF amps, this thing, connected to about 75 feet of longwire antenna will pick up Radio Pluto, if the Plutonomiums have a HF transmitter on the air.
::Lewis
::
:

Have done a lot of the Hallicrafters radios. The S-38's are AC/DC as well. Here is a link showing how to make that radio more safe. Easy modification.

http://www.the-s38-guy.com/Page_2.html

Lewis,

You can download a PDF file with the Riders S-77 and the Canadian RCC S-77A service information here:

http://www.nostalgiaair.org/resources/hallicrafters/hallicrafters-S-77.pdf

Hope this helps!

Richard