Thanks............
The 6SQ7 "balancing exciter" is just a phase inverter to drive the bottom p-p output tube. (I'm unfamiliar with their term "balancing exciter," but so be it.) I don't think that this tube being a little weak would be your problem. But I notice there is another 6SQ7 in the lineup, so just swap them and see if it makes a difference.
Is the problem that the volume is weak or that the volume is OK, but you just can't tune weak stations? Misalignment can cause low volume, so that would be worth checking.
:Here's your schematic: http://www.nostalgiaair.org/PagesByModel/148/M0011148.pdf This is a nice set with push-pull output tubes and a tuning eye. I think that the "WG" in the model number means that it was built by Wells-Gardner.
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:The 6SQ7 "balancing exciter" is just a phase inverter to drive the bottom p-p output tube. (I'm unfamiliar with their term "balancing exciter," but so be it.) I don't think that this tube being a little weak would be your problem. But I notice there is another 6SQ7 in the lineup, so just swap them and see if it makes a difference.
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:Is the problem that the volume is weak or that the volume is OK, but you just can't tune weak stations? Misalignment can cause low volume, so that would be worth checking.
This is incredible!! I'm, also, restoring the same model radio and determined that it is of Well Gardner manufacture, but, could not find a schematic for it. Stamped on the chassis is "8A55", which looks like a WG model, but, I couldn't find it in WG research.
I, too, was curious about the term "balancing exciter", did a Google on the term, and landed here!! What do I find here, but, a schematic of the radio. WOW!! I've been working with 'similar' schems, but, not the THE right one. Now, I can answer some lingering questions. This site rocks!! Thanks, guys!
73, Mike K 0 Collects Radios eXclusively
What is the actual broadcast frequency of that station?
About where on the dial does in come in on?
The other stations that you receive, do they appear about where they should on the dial?
Also consulting the schematic, and perusing over in a purely improvisatory manner …sort of sounds like RFitis, IFitis,AGCitis, Mixer grid
LC or contactitis … initially, how’s about confirming the “health” of most all of your audio processing function and its adjunct power supply
feeds by seeing if that designated phono input connector on the chassis rear is the common RCA jack and get a 500mv-1VAC audio
sourcing from either an audio CD player or only one AF lead of a DVD player and plug it in the phono input. Then put the input selector
sw in the phono position and evaluate. That system should then be able to” knock ‘yer socks off” if in pristine condition, as per the AF
design aspect capabilities.
Passing that audio evaluation, having already said that you own a HOOLET PLASTERED R.F. GENERATOR (Bow three times facing
Mecca….or initiate three Hail Mary’s…or a simple… Thank You Jesus!….. for my good fortune, will aptly suffice.)
Put the receiver in BCB receive mode and take Mr HP’s RF outputly connector in hand….hopefully with the alligatoring clip adapter
leads… and merely make a loose capacitive coupling into the IF amp input stage by clip connecting externally onto the insulated wire
from the first IF transformer to the IF’s first grid.
Set up the Gen RF out to ~456kc modulated and use the decade and vernier attenuators to bring up the RF level while observing your
tuning eye. Hopefully you might then be able to get close to closing the eye tubes display, in the interim, while the adjunct din from the
speaker is driving you bonkers.
A trained/experienced operator should then be able to merely drop below 456 and then tune onto it and then past it while observing the eye
tube indication and be able to make an evaluation of the IF health of the three tuned stages involved. It should have gain coming up fast and
a sharp peak and then a like diminishment as tuned past it…the alignment response slope being much in the order of the side profile of a
sharpened wooden pencil. That response would be indicative of a “healthy” stage devoid of any “diddling” to have misaligned it, or any
companion LC tuning component defects.
With that stage evaluation kept in mind as to required gen injection level, attenuate the gen RF input level to the point of an ~ ¼ closure of the
eye tube. Then you walk the RF over to the firstus grid of the mixer where I hope there will be a spaghetti/macaroni
insulation the bare wire lead if C8 (or its companion 2.2 meg AVC grid return resistor) such that you can initiate the same loose input coupling
technique, if not slit a piece and make it that way .At this time, that RF gain of the mixer stage plus the additive resonance of the plate circuit
IF transformer should have brought gain displayed on the eye tube up with a perceived presence of additional gain.
Past that, you would want to make a like evaluation of the very few RF components in the 540-1720 RF handling circuitry….specifically T7
your sets loop aerial condition and its connections…very important.. as well as band switching contact integrity.
A quick check of an AVC related gain compromising condition could be initiated by a tune in to a moderate strength station signal and finding
the common juncture of R5,C21A and T4 IF xformers connecting lead. Shorting that to ground should let IF and RF stages run at full unbridled
gain and confirm if there was any abject excessive gain attenuation via the units AVC circuitry.
Also curious about your described reception (image) , as was Sir Douglas. In the interim before any refreshing feedback, if there was any
station reception in the 540-~700kc spectrum, you might tune to it and take a pocket AM battery powered Xstr radio and bring its ferri loop
antenna close to the BCB osc coil. Tune 456 kc up from the received signal and listen for the distinctive carrier quieting on the xstr radio and
then tune completely up and down the xstr dial to see if there might be any other Osc carrier harmonics. This all being disregarded in case you
have a 50KW powerhouse in your proximity or a fore mentioned LC constants problem in your mixer grid circuitry.
BTW…..”I completed a repair to a Montgomery Ward 14WG-807.”…….what was that repair?….possibly cause related ?
73’s de Edd
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:I completed a repair to a Montgomery Ward 14WG-807. I am picking up only "strong" stations even with an antenna. Also the strongest station, I can recieve at 3 locations across the dial. Is this an indication that I need an alignment? Or could I have a problem with my 6SQ7 balancing exciter, which is on the weak side. I have an HP signal generator available, if I need to re-align. Just would like a second or third option.
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:Thanks............