01-20-2008, 05:07 PM
Is there any means by which to align a Philco 620 radio without the use of a signal generator. I have one, but don't know how to use it . Any thoughts out there on how to align the set? Thanks
01-20-2008, 05:07 PM
01-20-2008, 08:19 PM
Hi David,
You will need the signal generator to align the IF stages. Radio stations of known frequency can be used for the other adjustments such as the antenna trimmers. Not a recommended beginner's radio given all its bands. May want to try aligning the simpler AA5 radio first to get familiar with your signal generator and making basic adjustments.
Richard
You will need the signal generator to align the IF stages. Radio stations of known frequency can be used for the other adjustments such as the antenna trimmers. Not a recommended beginner's radio given all its bands. May want to try aligning the simpler AA5 radio first to get familiar with your signal generator and making basic adjustments.
Richard
01-21-2008, 10:45 AM
Be aware that signal generators are very often not accurate so it may not be wise to do adjustments without verifying the dial. For your 620 you will need 460KHz with AM . Aligning the IF properly is VERY important so I suggest that you don't try it without borrowing someone's frequency counter first. (shut the AM off when using the counter). A last note on your 620 IF- once you align it, NEVER go back and tweak it for better reception anywhere on the dial.
The 620 is an excellent radio! Depending on where you are located and what you use for an antenna, you should be able to pick up stations from several continents with ease.
DON'T CLEAN THE DIAL WITH ANY LIQUID!!!! Just use a dry brush to get rid of dust. New dials are readily available but the originals are still nicer.
The 620 is an excellent radio! Depending on where you are located and what you use for an antenna, you should be able to pick up stations from several continents with ease.
DON'T CLEAN THE DIAL WITH ANY LIQUID!!!! Just use a dry brush to get rid of dust. New dials are readily available but the originals are still nicer.
01-21-2008, 06:20 PM
Thanks for the advice, would you consider the alignment of a radio a necessary step in restoring it? I am repalcing all the caps, one tube, and the rest of it seems in pretty good shape. I refinished the cabinet, repaired the speaker and replacing the grill cloth. Should I leave well enough alone or try aligning it to get better reception. At present it seems to tune quite a few stations, but it drifts quite readily once a station is tuned in. I tried reading the manual to the signal generator a Military UA 25, but I don't comprehend how to use it to align a radio. You mentioned the IF stages and antenna trimmers, perhaps I should only adjust the antenna trimmer and leave the IF's alone. About the face dial, I wish I knew then what you told me today, I partially ruined the dial by trying to clean it. Whats your thoughts on finishing the restoration of the radio?
01-22-2008, 11:37 PM
Hi David.
I seen your other post. Please be patient for someone to answer.
I'd would suggest that you look for a signal generator. Ebay and other sources have generators that are pretty reasonable. It is one of those things that you buy, and will always use.
It doesn't have to be anything fancy either. Something good enough to hold a good signal, and be fairly accurate is what you need.
I am not familiar with that military unit. It may be more than you need or could be for more specialized equipment.
You need something more simple to operate, and once you have used it to align a set, you will be glad you did.
Aligning a set can do more harm than good if you don't know what you're doing.
If you only did a recap of most of the paper caps , then an alignment may not be necessary at all. If it is, only small tweaking adjustments may be needed. Just a tiny amount is often needed to peak the signal, if at all.
The IF should be just about where it should be, unless someone has fooled with the screws already.
If for example someone replaced all the caps in the RF section (which is usually unnecessary in what we do) then a total alignment would be necessary.
Keep an eye out for a good signal generator or place an ad in the classified sections of radio forums.
Good luck.
I seen your other post. Please be patient for someone to answer.
I'd would suggest that you look for a signal generator. Ebay and other sources have generators that are pretty reasonable. It is one of those things that you buy, and will always use.
It doesn't have to be anything fancy either. Something good enough to hold a good signal, and be fairly accurate is what you need.
I am not familiar with that military unit. It may be more than you need or could be for more specialized equipment.
You need something more simple to operate, and once you have used it to align a set, you will be glad you did.
Aligning a set can do more harm than good if you don't know what you're doing.
If you only did a recap of most of the paper caps , then an alignment may not be necessary at all. If it is, only small tweaking adjustments may be needed. Just a tiny amount is often needed to peak the signal, if at all.
The IF should be just about where it should be, unless someone has fooled with the screws already.
If for example someone replaced all the caps in the RF section (which is usually unnecessary in what we do) then a total alignment would be necessary.
Keep an eye out for a good signal generator or place an ad in the classified sections of radio forums.
Good luck.