Yes it is common on that type of circuit. Modern strong stations can be picked up after a volume control.
On your radio it's a little different. Volume control also adjusts bias on cathode of your IF stage. Does this voltage vary? The 25K resistor from your control to B+ may be open?
Norm
:hi i have got my majestic 15 working well except for one thing the vol. on this set is controled off of the ant.as you turn it up it works but has too much gain on strong stations it would blast you out of the room is this common for this type of circut?i don't think it has any avc circut so maybe this is the problem i guess i change the pot. or experment with res.on that circut or just leave it alone and be careful turning up the vol. by the way thanks for sending me to the playthings of the past site, norm that xformer worked far better than my homemade one.butch
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::hi i have got my majestic 15 working well except for one thing the vol. on this set is controled off of the ant.as you turn it up it works but has too much gain on strong stations it would blast you out of the room is this common for this type of circut?i don't think it has any avc circut so maybe this is the problem i guess i change the pot. or experment with res.on that circut or just leave it alone and be careful turning up the vol. by the way thanks for sending me to the playthings of the past site, norm that xformer worked far better than my homemade one.butch
Measure cathode voltage on your IF amplifier, 35/51 tube. Pin #4 should vary as you adjust volume. Around 35-40 volts your IF stage should cut off. (No sound out of the speaker.) Make sure at min volume voltage is near this level.
25K wouldn't be a modern standard value resistor unless it is wire wound. Do you know what value AES supplied?
Norm
::Hi Butch
::
:: Yes it is common on that type of circuit. Modern strong stations can be picked up after a volume control.
::
:: On your radio it's a little different. Volume control also adjusts bias on cathode of your IF stage. Does this voltage vary? The 25K resistor from your control to B+ may be open?
::
::Norm
::hi no the the 25k res. is not open i had replaced it with a new 1 watt from aes however looking closer at the schematic i see the cap from the cathode of the 51 to ground may be a 1 mfd i used a .1 mfd i can't tell for sure as my schematic is kind of blurry i could try changing it to see what happens.i'll have to check the voltage as you sugested as soon as i get the speaker hooked back up however as the volume control is working about halfway i don't think this is the problem but then again.butch
:
:
:
::
:::hi i have got my majestic 15 working well except for one thing the vol. on this set is controled off of the ant.as you turn it up it works but has too much gain on strong stations it would blast you out of the room is this common for this type of circut?i don't think it has any avc circut so maybe this is the problem i guess i change the pot. or experment with res.on that circut or just leave it alone and be careful turning up the vol. by the way thanks for sending me to the playthings of the past site, norm that xformer worked far better than my homemade one.butch
hi norm the res. i put in was 27k i checked cathode v. at lowest volume it is 53 v. at max volume it is 5 v. and the sound does cut off at 40 to 45 v. i think maybe i'm worried about nothing it works very well on most stations its just on a few strong ones the volume goes very high i guess i'm not used to an old set having this kind of volume much over 3/4 volume on a strong station hurts your ears i'm suprised the speaker handles it.of course when i got this set the caps were right but almost all the res. had been changed and none were the right values 2 of them wern't even there i wasn't sure i had the right schematic but the pict. was the same.i guess on stong stations i could flip the local/ distance switch.i have replaced every res. and cap in it and done a good deal of rewiring so its possible i still have something wrong but it works good and is very sensitive maybe too sensitive.oh the 27 k res. i used was a carbon film res.butch
:::Hi Butch
:::
::: Yes it is common on that type of circuit. Modern strong stations can be picked up after a volume control.
:::
::: On your radio it's a little different. Volume control also adjusts bias on cathode of your IF stage. Does this voltage vary? The 25K resistor from your control to B+ may be open?
:::
:::Norm
:::hi no the the 25k res. is not open i had replaced it with a new 1 watt from aes however looking closer at the schematic i see the cap from the cathode of the 51 to ground may be a 1 mfd i used a .1 mfd i can't tell for sure as my schematic is kind of blurry i could try changing it to see what happens.i'll have to check the voltage as you sugested as soon as i get the speaker hooked back up however as the volume control is working about halfway i don't think this is the problem but then again.butch
::
::
::
:::
::::hi i have got my majestic 15 working well except for one thing the vol. on this set is controled off of the ant.as you turn it up it works but has too much gain on strong stations it would blast you out of the room is this common for this type of circut?i don't think it has any avc circut so maybe this is the problem i guess i change the pot. or experment with res.on that circut or just leave it alone and be careful turning up the vol. by the way thanks for sending me to the playthings of the past site, norm that xformer worked far better than my homemade one.butch
Do you still have this problem even with a short or non-existant antenna? Whether you do or not, you can try placing a piece of sheet metal or aluminum foil below the chassis that will contact the chassis, so that no stray signals may wander into the circuitry. Regardless of how much the antenna is allowed to operate as you turn the control up, there may be so much of a local signal getting under the chassis that as soon as you lower the cathode bias enough, this will jump right through the set.
Just a thought.
Thomas
Think your radio is operating properly. These radios didn't have AVC so you will have a big difference in volume between strong & weak stations.
Norm
:I was going to suggest raising the value of the pot. so that as you turn up the volume, the antenna will be ungrounded before cathode bias is reduced significantly, but since nothing will be heard below cut-off, this wouldn't likely improve anything anyway. Lowering the value of the pot. may improve things, but will likely reduce sensitivity, as this will put less resistance between the antenna and the chassis.
:
:Do you still have this problem even with a short or non-existant antenna? Whether you do or not, you can try placing a piece of sheet metal or aluminum foil below the chassis that will contact the chassis, so that no stray signals may wander into the circuitry. Regardless of how much the antenna is allowed to operate as you turn the control up, there may be so much of a local signal getting under the chassis that as soon as you lower the cathode bias enough, this will jump right through the set.
:
:Just a thought.
:
:Thomas
hi and thanks for the replies i think norms right there is nothing wrong with the set it is just a very good radio at least compared to some of the similer sets i have as thomas said i don't have a problem with a short ant. and also when i get a strong station i can switch the dx local switch to local and it works fine.then too i almost totally rebuilt this one the others i replaced electrolytics and a few things and when they worked i thought good enough maybe all new components would help some of the others too,but i'm satisfied with this one i have always liked grunows and majestics and they all have been good sets even the majestic 132 i had was a heck of a radio well thanks again . butch