Geeze, that radio is going to be like freaking MINT when you are done with it!!! I love seeing this going on and these sets not just throwen away!! Wonderful work you do, you should open up a shop :)
Generally you don't trigger your scope. Instead you put it in XY mode and connect the X and Y to outputs of the sweep gen. Some use the AC line for the sweep and you can trigger your scope to the ac line too and use a phase control to compensate for any phase delay.
I have got to get that sweep gen. I also have a senior voltohmyst I am having issues with. I just might do a video so I can get some help. Never used one before and am a bit lost I must confess. Another awesome video!!!! Very informative.
Nice work, most of my old tube radios just stay on the shelf without much use since i dont like the programming on the radio so my repairs usually just consist of recapping and getting them running again and, and they do fine but ive never bothered to actually go in and tweak them back up to spec. Looks like it makes a world of difference. This video has me interested in doing that now. Also i WOULD love to see you make a video on the procedure using the vtvm.
I usually tune up and align my sets because I like to tune listen to long distance broadcasts or DX as the hams call it.. It's well worth doing especially if your set has some shortwave bands. I'm used to doing it by ear because for years I did not have a scope, there is a trick to it in that you go back to the generator and reduce the output level then to the radio to readjust the IF cans in stages, a scope is definitely faster.
I believe the retail price is around $6,500. Used in full working condition they go for $1,000 - 2,000. Unknown or partially working, under $500. I see one sold recently for $125 but the CW mode wasn't working. Keep in mind it can cost a couple grand to have one repaired and calibrated.
it's going to vary somewhat from radio to radio. The basic idea is to feed a swept signal around +/- 10% of the IF frequency before the first 1F stage and place the scope after the detector. The key is to peak the IF coils at a specific frequency (typically 455). This can be done with just an RF generator and VTVM so most alignment instructions don't include visual instructions.
I've only used an RCA WR-50B for AM alignment once or twice. Mostly I just use a standard RF generator for alignment. I've heard the Sencore SG165 is good but have never used one.
@bandersentv I'll be gosh darn it does mention visual alignment of the AM section. amazing! For AM R-F (front end) visual alignment, step 10 it says sweep.... +/- 20 Khz. I will be gosh darned. Ha ha. Love it. I will try that on other radios. Cheers
You've now peak tuned the IF transformers rather than stagger tuned them as they probably should be to accommodate the wide bandwidth AM broadcast stations. You need a sweep gen, wobbulator or spec analyser with tracking generator. You have to be able to see the shape of the IF passband to set the IF transformers.
That is the coolest alignment method I''ve seen. I want to try that, but I can't remember if my generator supports sweep. Have you ever done FM stereo alignment? I don't think I've seen anyone do that yet.
I really enjoy ur features, thanks for posting and sharing this info. I wud like to pick up a suitable sweep gen that will do 455-465 sweeps for am sets, and 10.7 MHz for the fm sets. Can you recommend something that will be suitable in the 1-300 buck price range? Perhaps something you have experience with? I have purchased 2 already from eBay, both wavetek, and both not working, haha.
The problem I had with the RCA WR50B us the sweep is not linear but the scope (in line sweep) is. How did you get the WR50B to work? What radio is it? Sorry for all the questions, I am totally fascinated you got it to work... again great video.
Are you using a RCA WR50B to sweep AM! How do you know where you are, meaning marker? I had one; never got it to work correctly. I use a HP 3336C (synthetic signal sweep). I also have a Sencore SG165 which does FM IF's only (10.7 Mhz). Both work well. GREAT video! Did the radio actually give you visual alignment steps for AM section? That's amazing. Working on Zeniths tube AM/FM they don't even give you visual alignment steps for FM in the "factory" info (you have to get a SAM photofact).
Also, if you do another video of this type, it would be helpful for me to know your o-scope time settings, and how you sync the response curve with the scope, ie what trigger settings you use etcetera..
Hello I am watching a wavetek sweep generator like you have the digital readout about how much did you pay ? just wondering whats it worth nok Thankyou Dennis
Thanks for the videos. I am really learning. Would you please tell us where you hooked the sig gen to and where you hooked the scope to. I would like to align my AM sets in this manner but none of mine have visual alignment instructions. Thank you.
I am about to purchase the RCA WR-50B, Bob, I truly love all your videos, you are a master at what you do, could you please tell us detailed info on how you set the RCA generator for sweep say from 400 to 500KC? thanks so much!
I connected it as indicated in the alignment instructions for this GE 212 radio. I don't recall the exact point on the schematic. It's going to be different for every radio. Not sure you mean by "attached to the insulation" ? The scope probe is making contact directly to the circuit.
Nice video. I have a Heathkit shortwave receiver that I built in 1988 I think. I do not have an oscilloscope. Do you know of a way to align it with just a digital meter?
Generally speaking, alignments are done with analog meters rather than oscilloscopes because it's easy to watch the needle moving while peaking the coils. You can do it with a DMM too, but it's not as easy - especially if it has a slow refresh rate. I'm not familiar with more modern receivers like yours to get any more specific. Maybe try asking on the Antique Radio Forum ?
At 3:45 you say you are SWEEPING the front end, antenna trimmer? Can you direct me to those instructions.. My pet topic is sweep alignment. All the instructions I have say to use a single Freq and tone, audio peak for the front. The sweep is just for the IF (so I thought). I like your way better! SORRY for the three posts.
Yes, it does look there is DC offset. It's been years since I made this video and don't remember the details. I expect it is something to do with the vintage sweep generator I'm using. Coupling through a capacitor will block it,
And part of your video. Am I hearing a inverter generator running in the background. The reason why I ask is I do the same thing. That's how I run my shop. I'm curious it's doing it that way cause problems on the oscilloscope. Prior to testing any circuits.
I like your use of vintage test gear. I have been spoiled with all of my HP and Tektronix gear in my shop but I remember well getting by just fine with less cash tied up in equipment..Great video What is the model number of the RCA sweep gen?? My first VTVM was an RCA VoltOhmist that I got for Christmas when I was in the 5th grade, COOL PARENTS!! I still have it with the matching audio volt meter. Do you happen to be a Ham op? Best regards, Glenn WA4AOS DSM Labs (dot com)
Hi. It's an RCA WR-50B which I sold a while back. More recently I've been using a fairly modern HP3336A synthesized sweep generator for radio alignments. It's a little overkill but a cool piece of equipment to have. No, I'm not a ham but I've been to plenty of hamfests and am familiar with the community. Maybe someday.
bandersentv It's a great hobby and you will be a true asset to the Ham bands..I encourage you to get a licenses.You already have the knowledge for the electronics part. 73, Glenn WA4AOS
Kennynva T. The hook-up is different for every chassis. The service info will have detailed instructions on where to connect the RF generator and scope
Kennynva T. Scopes have been around since the 30s but we're an expensive luxury for they average radio tech. So you're right, the alignment instructions probably only cover using a VTVM. That's all you really need anyway since all you're doing is leaking coils at a specific frequency
If you can look at my radio diagram ,,,in the first section under IF alignment, on step 2 your will see what Im doing..the adjustment is "U"...I have a function generator/frequency counter on the way as we speak...maybe I can use that to find the exact frequency...
Set your RF generator to the IF frequency. Inject it into the converter or 1st IF stage. Hook the scope up to the detector. Adjust the IF slugs for the largest signal on the scope.
Thanks for another great video on radio repair techniques. Your dedication to detail and willingness to share is amazing.
Geeze, that radio is going to be like freaking MINT when you are done with it!!! I love seeing this going on and these sets not just throwen away!! Wonderful work you do, you should open up a shop :)
Generally you don't trigger your scope. Instead you put it in XY mode and connect the X and Y to outputs of the sweep gen. Some use the AC line for the sweep and you can trigger your scope to the ac line too and use a phase control to compensate for any phase delay.
I have got to get that sweep gen. I also have a senior voltohmyst I am having issues with. I just might do a video so I can get some help. Never used one before and am a bit lost I must confess. Another awesome video!!!! Very informative.
I do plan on doing another AM visual alignment video sometime soon using a Wavetek sweep generator. Maybe with my Philco 60MB.
Nice work, most of my old tube radios just stay on the shelf without much use since i dont like the programming on the radio so my repairs usually just consist of recapping and getting them running again and, and they do fine but ive never bothered to actually go in and tweak them back up to spec. Looks like it makes a world of difference. This video has me interested in doing that now.
Also i WOULD love to see you make a video on the procedure using the vtvm.
I usually tune up and align my sets because I like to tune listen to long distance broadcasts or DX as the hams call it.. It's well worth doing especially if your set has some shortwave bands. I'm used to doing it by ear because for years I did not have a scope, there is a trick to it in that you go back to the generator and reduce the output level then to the radio to readjust the IF cans in stages, a scope is definitely faster.
I believe the retail price is around $6,500. Used in full working condition they go for $1,000 - 2,000. Unknown or partially working, under $500. I see one sold recently for $125 but the CW mode wasn't working. Keep in mind it can cost a couple grand to have one repaired and calibrated.
it's going to vary somewhat from radio to radio. The basic idea is to feed a swept signal around +/- 10% of the IF frequency before the first 1F stage and place the scope after the detector. The key is to peak the IF coils at a specific frequency (typically 455). This can be done with just an RF generator and VTVM so most alignment instructions don't include visual instructions.
Thank you for sharing. I would like to see you do the other procedure using the volt meter.
Thanks
I've only used an RCA WR-50B for AM alignment once or twice. Mostly I just use a standard RF generator for alignment. I've heard the Sencore SG165 is good but have never used one.
@bandersentv
I'll be gosh darn it does mention visual alignment of the AM section. amazing! For AM R-F (front end) visual alignment, step 10 it says sweep.... +/- 20 Khz. I will be gosh darned. Ha ha. Love it. I will try that on other radios. Cheers
Use weak station to align too, many old timers now gone did it this way, it has benefits
You've now peak tuned the IF transformers rather than stagger tuned them as they probably should be to accommodate the wide bandwidth AM broadcast stations.
You need a sweep gen, wobbulator or spec analyser with tracking generator. You have to be able to see the shape of the IF passband to set the IF transformers.
That is the coolest alignment method I''ve seen. I want to try that, but I can't remember if my generator supports sweep.
Have you ever done FM stereo alignment? I don't think I've seen anyone do that yet.
I really enjoy ur features, thanks for posting and sharing this info. I wud like to pick up a suitable sweep gen that will do 455-465 sweeps for am sets, and 10.7 MHz for the fm sets. Can you recommend something that will be suitable in the 1-300 buck price range? Perhaps something you have experience with? I have purchased 2 already from eBay, both wavetek, and both not working, haha.
The problem I had with the RCA WR50B us the sweep is not linear but the scope (in line sweep) is. How did you get the WR50B to work?
What radio is it?
Sorry for all the questions, I am totally fascinated you got it to work... again great video.
Are you using a RCA WR50B to sweep AM! How do you know where you are, meaning marker? I had one; never got it to work correctly. I use a HP 3336C (synthetic signal sweep). I also have a Sencore SG165 which does FM IF's only (10.7 Mhz). Both work well. GREAT video!
Did the radio actually give you visual alignment steps for AM section? That's amazing. Working on Zeniths tube AM/FM they don't even give you visual alignment steps for FM in the "factory" info (you have to get a SAM photofact).
Also, if you do another video of this type, it would be helpful for me to know your o-scope time settings, and how you sync the response curve with the scope, ie what trigger settings you use etcetera..
Hello
I am watching a wavetek sweep generator like you have the digital readout about how much did you pay ?
just wondering whats it worth nok
Thankyou
Dennis
Thanks for the videos. I am really learning. Would you please tell us where you hooked the sig gen to and where you hooked the scope to. I would like to align my AM sets in this manner but none of mine have visual alignment instructions.
Thank you.
I am about to purchase the RCA WR-50B, Bob, I truly love all your videos, you are a master at what you do, could you please tell us detailed info on how you set the RCA generator for sweep say from 400 to 500KC? thanks so much!
looks like you were on WLS???
Thanks for this video. Can you tell me where you had your oscilloscope attached for this video? Were you just attached to he insulation also. Thx John
I connected it as indicated in the alignment instructions for this GE 212 radio. I don't recall the exact point on the schematic. It's going to be different for every radio. Not sure you mean by "attached to the insulation" ? The scope probe is making contact directly to the circuit.
Nice video. I have a Heathkit shortwave receiver that I built in 1988 I think. I do not have an oscilloscope. Do you know of a way to align it with just a digital meter?
Generally speaking, alignments are done with analog meters rather than oscilloscopes because it's easy to watch the needle moving while peaking the coils. You can do it with a DMM too, but it's not as easy - especially if it has a slow refresh rate.
I'm not familiar with more modern receivers like yours to get any more specific. Maybe try asking on the Antique Radio Forum ?
At 3:45 you say you are SWEEPING the front end, antenna trimmer? Can you direct me to those instructions.. My pet topic is sweep alignment. All the instructions I have say to use a single Freq and tone, audio peak for the front. The sweep is just for the IF (so I thought). I like your way better! SORRY for the three posts.
On the top raw sweep trace, why and how are there elevated "skirts" up to and down from the sweep segments? It looks like a pos DC offset.
Yes, it does look there is DC offset. It's been years since I made this video and don't remember the details. I expect it is something to do with the vintage sweep generator I'm using. Coupling through a capacitor will block it,
Thank you for the reply! I have learned so much watching your video "classes"! These are great.
Pearl Harbor day my ass, you tuned the damn thing back to 1941! Now build a transmitter and tell my parents to buy IBM stock!
And part of your video. Am I hearing a inverter generator running in the background. The reason why I ask is I do the same thing. That's how I run my shop. I'm curious it's doing it that way cause problems on the oscilloscope. Prior to testing any circuits.
No, that's either the cooling fan in the scope or my forced air heating system you hear.
Blasting for you, maybe, but I can barely hear the results. Tnx for the video.
I like your use of vintage test gear. I have been spoiled with all of my HP and Tektronix gear in my shop but I remember well getting by just fine with less cash tied up in equipment..Great video
What is the model number of the RCA sweep gen?? My first VTVM was an RCA VoltOhmist that I got for Christmas when I was in the 5th grade, COOL PARENTS!! I still have it with the matching audio volt meter.
Do you happen to be a Ham op?
Best regards,
Glenn WA4AOS
DSM Labs (dot com)
Hi. It's an RCA WR-50B which I sold a while back. More recently I've been using a fairly modern HP3336A synthesized sweep generator for radio alignments. It's a little overkill but a cool piece of equipment to have.
No, I'm not a ham but I've been to plenty of hamfests and am familiar with the community. Maybe someday.
bandersentv It's a great hobby and you will be a true asset to the Ham bands..I encourage you to get a licenses.You already have the knowledge for the electronics part.
73,
Glenn WA4AOS
Hi..where do you actually hook the scope wires to do this alignment???
Kennynva T. The hook-up is different for every chassis. The service info will have detailed instructions on where to connect the RF generator and scope
This is a 1950 radio...all tube's I doubt they had O scopes then..or they did not have it in the alignment instructions..
Kennynva T. Scopes have been around since the 30s but we're an expensive luxury for they average radio tech. So you're right, the alignment instructions probably only cover using a VTVM. That's all you really need anyway since all you're doing is leaking coils at a specific frequency
If you can look at my radio diagram ,,,in the first section under IF alignment, on step 2 your will see what Im doing..the adjustment is "U"...I have a function generator/frequency counter on the way as we speak...maybe I can use that to find the exact frequency...
Kennynva T. Sorry, I don't know what model radio you have. 455 kHz is the standard IF frequency
I dont understand how you use the scope with a regular RF generator...not a sweep generator.
Set your RF generator to the IF frequency. Inject it into the converter or 1st IF stage. Hook the scope up to the detector. Adjust the IF slugs for the largest signal on the scope.
Basically use the scope in place of the VTVM in the alignment instructions.
Is there a way you could look at a Panasonic RF-2200 diagram and tell me where the two points are please...thanks