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I have this radio all recapped and it plays good except the stations don’t show up on the dial in the right place.
It is a Westinghouse table model 675I have gone through the RCC disk and tried all the places where I usually find schematics,but can’t find this one.
I have the schematic but it does not give me the information I need.
Thanks
Dan in CalgaryMorning Dan
How far off is the Dial Poiner. Your problem seems to be pointing to the Alignment of the Oscillator on the Dual Gang Tuning Condenser or to problems with Induction variances on the Broad Cast Oscillator Coil. (‘A’ band) . The Schematic and the Alignment Procedure for the Model 683 is, and should be the same as is required for your Model 675The following in Red Font is the actual wording on the original Westinghouse Service Manual. Alignment Procedure, for Model W683, which should be very close to that of the Schematic for your W675. These two Radios manufactured about seven years aparte are almost identical, in tube line-up and cabinet design. Any Notes in Brackets are my wording.
Calibrate the tuning dial by adjusting the pointer to the low frequency end of scale with gang condenser plates fully meshed. The pointer should be set at the end of the horizontal line, ( Note: It does not say which horizontal Line or for which Band the Adjustment is made, but they all seem to be the same length anyway) Adjustment is made by loosening the dial drum on the shaft.
Perform alignment in proper order as shown by the accompanying chart. ( Which you don’t have but which, but wich should possibly be identical to that of the same chart for the Model W683 which I am holding in my hand) Note Alignment Positions #s 1 and 2, relate to IF Alignment at 460KC, which for you seems very close to being accurate, as you said the sound comes in loud and clear. This, I think, points the finger at Oscillator section of the tuning Condenser trimmer adjustment on that section of the Tuning Condenser. Adjusting this screw to the left or to the right should move the Frequency Signal to move to the Left or to the Right on the Radio Dial) Dan, how far off is the dial alignment???
There s one more thing which I think could affect the accuracy of the pointer on the dial. I am referring to Alignment Position on my Alignment Chart for the ModelW683, which is what Westinghouse refers to Adjustment Point # 5. This adjustment is made by adjusting the gap on the top turn of the Broad Cast Oscillator Coil which is, I suppose, the turn closest to the metal Pan /Cover/ Shield they use on these radios. They refer to it as bending the wire turn or loop either Up or Down. This procedure, because it is part of the Alignment Process, may be the cause of your problem, About three weeks ago I was attempting to adjust the dial on a transistor radio, when I noticed that on the Oscillator Coil it looked like someone had tampered with the winding. I straightened it out and the Dial Alignment was worse than before. A re-adjustment in the other direction cured the problem.
The General Alignment Procedure, on the brochures for most of these Canadian Westinghouse Radios use the same wording. The only difference on the Alignment Procedure Chart is the location of said adjustment screws/etc. on any particular chassis.
I would send you a copy of this Procedure Chart and the Schematic for the W683 Chassis, but I cannot get the scanner on my Printer to “Scan to Document”
PS: When I purchased my W780Y Radio about 40 years ago, it came with a binder containing most Canadian Westinghouse Schematics for the era from 1935 to 1948, some, of which aee even earlier. But somehow I have misplaced the Schematic for your W675 Model and that of my own W780Y.
Hope you don’t get lost in what I am trying to say. But it really is not complicated.
RalphHi Ralph; The location of the adjustment screws is a problem. The adjustment screws are there , but knowing which on to adjust with the signal generator
set at a certain setting is part of the problem. I had to restring the radio and I can set the pointer where I want , but I still need the information telling me which
Adjustment to make
thanks
DanHere are a couple of photos showing what I have.
DanDan
I am still hoping to find that lost 675 Schematic and Service Bulletin,which covers Alignment, Re-stringing and a wiring diagram. You never responded to my question about how far off the Station you were listening to, and that of where the pointer was on the dial. Is it possible that the tuning drum is installed backwards? This could cause a like problem to what you are describing. Also if the take-up rotating string shaft, usually set around 2-2 1/2 turns. is being fed from the wrong side, this too could cause a similar problem. The stringing diagram of this radio, while being fairly simple, can still be subject to mistakes.
Also, has anyone tampered with the twisted pair of wires from Pins 5 and 8 of the 6BA6. W/house used this pair of twisted wires (black if I remember correctly) on many of their Radio Sets. It acts as a capacitor. I am not certain however if it could cause the problem you are trying to correct. The capacitance can be adjusted by snipping away a portion of the twisted pair, Hopefully you do not need to resort to this particular action. Not all models have this twisted pair. So far I have not found the need to adjust length of these leads.. This I think is going to be a process of elimination as you move forward.
Ralph
Dan
Is this the Identifying of Alignment points and coils you are looking for? I found them on the Radio Museaum Site.Regards
RalphSorry about that. It did not send the pic. It was right in front of us there, on the Radio Museaum Site. Do you have the proper sequence for the Alignment? I would think, that fpr starters you could bypass the 460 KC Alignment, as according to what you said, they may be dead on. Note: Also when making any RF adjustments, the bottom Shield Pan must be in place. The locations andfrequencies when making these R F Adjustments are shown on th sticker fastened to the bottom side of the chassis shield pan. I am supposing that, that sticker is in place.
Ralph
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