Rebuilding an SB-220 (for KJP)

Discussion in 'Amateur Radio Amplifiers' started by W1QJ, Jan 19, 2013.

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  1. W1QJ

    W1QJ Ham Member QRZ Page

    While we are on the heated subject of rebuilding old SB-220 amps and hashing over the "beyond stupid" prices of parts I would like to offer the latest on a rebuild project. A ham contacted me saying he had just bought an SB-220. He said he wanted it "totally rebuilt". I asked about any specific problems with the amp that needed to be addressed and perhaps we could do some simple repairs to get it up and running. He said he never plugged it in and "I just want it rebuit with all new parts". He said he would ship me the amp and that he was going to call Jeff at Harbach and have him ship me all the parts he wanted replaced. Since he never plugged the unit in and wouldn't, I just waited until everything arrived from Jeff. One day several boxes arrived. Here is what I was sent. 1. One Peter Dahl HV transformer 2. One Peter Dahl filament transformer 3. One Harbach replacement rectifier board 4. One Harbach replacement capacitor bank 5. One Harbach soft key 6. One Harbach step start module 7. One Harbach replacement fan assembly. I received the amp as well. Naturally I had to build all the items that come in kit form and then remove all the old parts and then install all the newly built kits. It's all completed now and the amp is running. DO THE MATH. I'm sure we all agree that for the dollars laid out between the initial buy of the amp, all the transfomers and kits and the labor, this gent could have bought a nice used amp of another brand that would have blown away an SB-220. Hey, I tried but he insisted. Should I have refused to do this? According to KJP maybe I should have since according to him, this is "beyond stupid". I suppose it takes all types to make a world. How boring it would be if we were all alike. Take it away dude.
     
  2. WB2WIK

    WB2WIK Platinum Subscriber Platinum Subscriber QRZ Page

    Lou, I can't believe one of the most desired mods for a 220 isn't 6:1 planetary reduction drives for the two tuning controls.

    When I get a 220 in, it's the first thing I do. $12 each or less, a few mins with a drill, and bingo. What a difference.:eek:

    You are doing a great service to hams who evidently don't own a soldering iron or a screwdriver, and I commend you for it.
     
  3. W1QJ

    W1QJ Ham Member QRZ Page

    Steve, Thanks, believe it or not I have a regular 9-5 job which is TOTALLY unrelated to ham radio in any way shape or form. I got into ham radio when I was 13. My cousin introduced me to it when I was 12. Got my novice (good for only one year) then general. Then incentive licensing took away my privligages so got advanced then phase 2 took them away again so had to get Extra. When I got my general I parked on 75M AM with the great HLR and the rest of the peanuts whistles. WHen I got talked out on AM I bought my first SSB rig (NCX-3). I discovered DX. I went hook line and sinker for it. I lived for DX for sevral years. I was obsessed. After obtaining honor roll status I didn't know what else to do so I started tinkering with amplifers because I was also a drag racer at the time. SO like powerful cars I took a liking to powerful amplfiers. In an effort to "help" a friend who wanted more power on 6 meters I discovered an article written by WB2PAG. I am sure you know him from when you lived on the east coast. Since my friend had an SB-220 that was replaced by an AL-1500 he let me experiment with the WB2PAG 6 meter mod. Long story short we got it to work after several bouts with parasitic suppressor fires (literally). Only problem was it wasn't very efficient and the tuning was so sharp you had to hold your breath when you turned the dials else your hand movement from breathing would make you miss the sweet tuning spot. He lived with that for a while but I knew there had to be something better than that. Thats when I went to the mono band design. Sure could have used those planetary drives then!! So I know what you mean. I would suppose anyone who owns an SB-220 and uses it on 15 or 10 knows what we mean. The tuning on those bands is only slightly better than what we had on the 6M mod. I agree that the amp should have them. I'd be glad to install them as you do. I'd think Ameritron is a good source for them. Ameritron is very good about selling parts!!! As you say 2 little holes drilled and you are good to go. Pretty much all Ameritrons have them. No skimp there. As to your other comment about hams not owning a soldering iron or a screwdriver. Unfortunately the hams who fall into this catagory are lambasted. Reality is that it is more prevalent than in days of yore but we have to face the reality of the times. So do we just continue to lambaste these people or do we come to the aid? Just like some people don't shovel their drivways of snow and mow their lawns or paint their house, they likewise don't want to work on their amps. Somebody has to do it. SO instead of me going back in time and BS'ing on 75M every night. And I 'm sure you will agree there is alot of that going on there on 75M. I use that time to take on the amplfier work these folks don't want to do. You'd be surprised the emails I get about amplifier problems. I try to encourage hams to make their own repairs or even take some simple measurements to determine the problems and have them fix it themselves. Often times they just want to send it out and have it fixed. They don't even want to be bothered taking the cover off. So like it or not that is the way it is. It's your choice you can lambaste them or you can provide the service they seek. I can tell you one thing, you won't make many friends by admonishing them for not wanting to DIY. I also do my share of Elmering as well! Lou
     
  4. KC8VWM

    KC8VWM Ham Member QRZ Page

    The missing link in your expressions is the fact that rebuilding an SB 220 for yourself is the entire idea you can learn something in the process. While I agree you could probably have slapped down a credit card to purchase something "that blows an SB-220 away," you can't really put a price on that experience, nor is such an experience available through VISA or Mastercard.

    Besides, the nice thing here is you now have a working amplifier that you rebuilt yourself, which basically translates to mean you will always have the intimate knowledge and capability to repair it yourself and with that said.. now let's do the math... :)
     
  5. NY7N

    NY7N Ham Member QRZ Page

    Personally, as someone who just picked up an old Heathkit amp (which fortunately was very well assembled and cared for by its previous owner), I'm glad there are folks like you out there who can be sources of parts and resources of information so folks like me don't have to resort to trolling ebay should something break.

    Illegitimi non carborundum and all that. :)
     
  6. W1QJ

    W1QJ Ham Member QRZ Page

    Charles you said the magic word "Mastercard" . Used SB-220 HV transformer $185.00 Used SB-220 filament transformer $75.00 New rectifier board $35.00 New capacitor bank $135.00 Soft key mod $27.00 etc.....KNOWLEDGE GAINED BY DOING THE WORK YOURSELF......PRICELESS!
     
  7. KC8VWM

    KC8VWM Ham Member QRZ Page

    I am in violent agreement Lou. :)

    Lou, I don't know if this will help or not but I think you deserve some feedback.

    For example, I have often studied your articles and threads and have learned a great deal from you myself. Your contributions to the amateur radio community are certainly recognized and yes they are indeed greatly appreciated. Keep up the great work and YES believe it or not, some of us out here are actually paying attention to what you are saying.... I hope that helps and please continue your work. :)

    My Best,
     
  8. W1QJ

    W1QJ Ham Member QRZ Page

    Thanks Charles that was really nice. I sure do appreciate it. It's this kind of a thing that makes it all worth while! Although I can diagnose just about any problem with an SB-220 or 200 without looking at a schematic (know them by heart) I have often times downloaded all sorts of schematics for other amps to study when someone has a problem with one I don't know by heart. I will then come back and offer some advice based on what I see on the schematic as to where to look for a problem related to the symptoms. I KNOW what it is like to have a non working piece of gear. It sure is nice and convient to come on the internet to a forum like this and get help and hopefully someone comes across with the fix. When I started out in ham radio in the 60's as a youngster and something went south on me I got an empty feeling in my gut. Sure you've had that. I couldn't turn on a computer and have the kind of help one can get these days. Heck if you didn't have a schematic for the gear you had to write the company for a manual. You were lucky if you could get one from them! We had to crack open the handbook and read it and maybe something would pop out to help you fix your problem. I know the value of the information that can be obtained here. I'm glad to be part of it. Likewise, I do get my share of help in return!
     
  9. KC8VWM

    KC8VWM Ham Member QRZ Page

    That's what I like about you Lou. You have everyone's best interests at heart at the end of the day. It is obvious you are passionate about our common interest and generally speaking, you are a great human being.

    It's a pleasure to have met your acquaintance and thank you very much for what you are doing. In my own evaluation, I consider your information to be as valuable and just as technically excellent as our mutual amplifier guru friend W8JI.

    Lou, I am looking forward to reading and studying more from you in the future.

    I hope you don't mind if I engage your technical expertise in the future.

    Sincerely.
     
    Last edited: Jan 19, 2013
  10. AH6RR

    AH6RR Ham Member QRZ Page

    Lou has helped me on some tough ones before and I can say that he gives his knowledge out freely. I completely rebuilt my 220 from the ground up after it had sat in a open carport in Hilo Hawaii up in the rain forest with a towel and a blanket covering it. It was a total basket case on the outside the paint was mostly black from mold and it was peeling everywhere. The good news was that it had a Peter Dalh filament transformer, Harbach Filter Caps and Soft start and fan it also had Eimac 3-500Z tubes in very good shape with bright red lettering. The bad news was the rectifier board was junk along with the plate choke and the Load cap was pitted and corroded badly. So I got a Harbach HV/Rectifier board, I made my own Plate choke with a piece of 5/8 Delrin rod and bought a load cap from MFJ/Ameritron. I completely disassembled the amp and cleaned the chassis because when the original filament trans melted down it left a nasty black residue. Along with the amp I did get the original manual so I went step by step just like the first person did to build it. I did replace all the ceramic disk caps and the resistors (My brother Bought all of Hammond Organ parts when they closed down so I had a free supply) for most of them. It was a lot of fun doing this rebuild after getting it most of the way built I added a home brew 12V keying circuit that keys the main relay. I then grounded the grids directly to the chassis after reading a few posts about doing it. Then it was time to Paint the face plate (sorry Sue I did not use Green:D) When I had questions both Lou and Tom W8JI were always the first to answer them. I had built a few amps back in my beginning days of radio and also some audio amps with the help of my brother, I built a couple of 100W single channel audio amp based off a dead Macintosh amp that would just about break the windows at half volume driving a pair of 15" JBL studio monitors ( I wish I had never sold them now) plus I was a electrician building oil refineries and offshore drilling platforms and was one of the HV crew doing mostly 14KV circuits so I do have a healthy respect for HV but I am not afraid to work on it. Well I got off subject some but I was dang proud of what I achieved on this rebuild and I am forever thankful to Lou and Tom both for their help and suggestions. Here are some pic's of the finished product.

    SB-2201.jpg sb2202.jpg sb2203.jpg

    Lou I hope you like coffee because a pound of the finest 100% Kona is coming your way:cool: for the tranny too.

    Roland AH6RR
     
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