[tubetwister]

QUOTE=dieseljeep;3188044]
I have one of those receivers in my warehouse, somewhere. I remember working on it and it had a floating B- line. Trying to remember if it's U/L listed.
On mine, someone replaced the 'lytic with a metal can type and installing it tied the B- to the chassis, which made it a shock hazard. I corrected that right away.[/QUOTE]

, that receiver was one of the last ones built in USA. They seemed to shift their production to Japan. Possibly, they used what left over![

Right AFAIK AA5 wasn't a metal Lytic ,that I recall and sometimes wax paper covered lytics laid in with the circuits instead of on top like this radio that sounds thats reckless or stupid on that radio you fixed good eye !


Setting aside the selenium rectifier and Zenith T.O. with an RF amp , the last AA5 tube radio was basically a clone of a 1936 reference AA5 even the Japanese radios and that time they were not uncommonly rubbish products anyway IRRC one could get get a chep no name or maybe regency Japanese or Taiwan AA5 for less than $10.00 in the mid '60s with the currency exchange rates back then.

IRRC Sony never made AA5 tube radios but I may be wrong and they got into the first Sony pocket transistor radios instead of rice cookers late like 1955 I think .

I read the Japanese S120 Hallicrafters AA4 had Japanese parts or a lot of them ,thats one way they said to tell if they had a Japanese made S120 AA4 or whatver

Those type of SWL receivers generally didn't sound that great, mainly they were made for speech or code reproduction and not really for music.

I had a number of boat anchors and comm, radios , 2 Hallicrafters S38 AA5 and a National Radio S54 AA5 and a Hammerlund HQ 170A (w/a squaker ) like all that and the marine radios on my offshore power boat money pitts I had so I know about comm. radio speakers and that audio.

OTOH This radio has elevated thd +n way more than it should or my other AA5 radios and the other radios above and the fixed hum that is too loud and garbles speech at the lower volumes .

Again SRSLY 50C5 beam power output tube has the Wrong value control grid cap and that cntrl. grid is over volting +6v + more if factor in the negative volt spec. but its a work in progress . I will know more with the new tubes and parts it could be tube and or circuit faults or something ahead of the 12AT7 AVC First audio contl. grid see below

The radio gives me the same distortion and same hum at the VoL. pot and center tap .head of the 50C5 output tube


Lets allow an argument that I didn't buy this deaf SWL AA4 for music . Bd'cast AM Frequency response is typically 40 Hz–7 kHz with a 50 dB S/N ratio at best and this radio can't make either end .

I been an Audio enthusiast since the mid 1960s & studied the popular digital audio codecs in depth more recently but not like what snob audio fools think hires is ,they knew what we could hear in 1950 and 16 bits is plenty if its done well ,

LOL those snob audio fools think they can hear different color tube plates in an amp with ~1% thd+n and a difference of adequate CT11000 copper wires & cables and AC cords vs the exotic metal cable fool stuff too and hires over good 16 bit in the same production but the industry is banking on those fools daily !

Lets allow an argument I may not the guy to be talking to about loudspeakers

Originally Posted by dieseljeep

I never worried about being electrocuted on a hot chassis receiver, as I've been doing it for over 60 years!
I also worked as an Industrial Electrician for 30 years, so I'm no stranger to even higher voltages.
I have one of those receivers in my warehouse, somewhere. I remember working on it and it had a floating B- line. Trying to remember if it's U/L listed.
On mine, someone replaced the 'lytic with a metal can type and installing it tied the B- to the chassis, which made it a shock hazard. I corrected that right away.

Lets allow an agrumant that if you have a post 1936 AA5 it wasn't basically any different at all than a 1936 AA5 unless it had an RF amp in the first tube on the radio side of the antenna like the Zenith T.O or a tone circuit pr phono in. or it was an AA6 variant but the same anyway as far as AC and B+ ,you can only do so much without a transformer in these .

I don't know if you attended electronics school but belive it or not we did learn some things an enthusiast may or may not know in some corners but we weren't on a TV radio curriculum for the most of it at all especially being near Silicon Valley if you know what I mean and we were all recruited back then ,

I changed study and career paths that ultimately paid and kept me more engaged and some would say well traveled
I ended up with a generous fortune 100 company corporate retirement plus , at 55


.

I never worried about being electrocuted on a hot chassis receiver, as I've been doing it for over 60 years!
I also worked as an Industrial Electrician for 30 years, so I'm no stranger to even higher voltages.

Well then ,then you must be very lucky or know what not to touch & how not to put yourself in harms way here with these lethal contraptions 99.99 % of consumers simply won't know today given that my radio is 52 yrs old and that would apply to a higher number of folks today without the tribal knowledge about all this so perhaps spreading FUD on web about all this or just minimizing this hazard anecdotally is reckless or no?

.

I never worried about being electrocuted on a hot chassis receiver, as I've been doing it for over 60 years!
I also worked as an Industrial Electrician for 30 years, so I'm no stranger to even higher voltages.

Lets allow an argument that aside from perhaps being reckless downplaying the lethal potential of these radios there may be folks without yours or an understanding of electrical current paths reading all this or have no idea what these 52 yr old plus radios can do to them without much provocation :

no need to debate all that ,the science around this is settled science )