I picked up an HW 7 from flea market. Sadly the output section was blown up, I had hard time find the MPSU transistors. but i found them also had replace emitter resistors and the base resistor on outputs, The RF choke had burnt up ad was able to rewind on with old contactor magnetic core wire. I admit i had tried some 2SC transistors first of but that did work out well i needed the MPSU 05 . It seemed the zener diode shorted too on the power dc line, being it is 13 volt type. for all practical purposes I was going use 12 volt dc battery so if you wish one can install the zener but i choose to leave it out as the radio will work fine fro 9 to 14 volts. so after that i go power output. The receiver had a problem when turning the varible cap frequncy A STRANGE SCRATCHING NOISE WAS AMPLIFIED THE THE RADIO I had to take the VC out and soak the bearings in gun wash and use fize brass brush to clean and the re grease it and assemble and re install. this cured the strange scratching noise while tuning. That preselctor is pretty touchy that way it is. as most will say put a larger know on it it helps. its the design but one can live with it , preselector is touchy. So after many hours of work and parts I did an alignment by the manual, some what impossible get band edges perfect but it is very well tune in the CW portion of the band anyway. Funny old tube receivers i did have perfect luck alignments but some times LC circuit needs work as well so I left the HW 7 as it good on CW bands pretty close is good enough Time of truth,, with a vertical antenna and a north america contest on 20 meters I go California , Colorado , Kansas new Jersy, /vermont , Ontario, few other place, WOW that was amazing on 2 watts or so , I tried 40 meters but no luck guess 40 got be pretty good get out on 2 or 3 watts. but the little HW 7 is a usable rig and contacts can be made, it can run on a alamr type battery for hours and hours and hours , great emergency rig if oyu need one. just my exepriance on the radio 73 Tony ve4akf
Useful info on things to look for, thanks! Got an HW7 myself which is a similar near-basket case. Going to be a winter-time repair project for sure, before I can put it in the shack next to it's younger brothers (HW8 and HW9).
I have rebuilt a few HW-7's and Hw-8's. I enjoy the Hw-7 when it is working. The biggest problem you will experience when you are done is that Heathkit did not engineer any transmit offset in the Hw-7. That is why the RIT mod was popular in that it allowed you to zero beat the calling station and also adjust the receiver. I have good success on 40 and 20 meters...15 meters is usable if the band is really open, but 20 meter signals will appear on 15 meters unless you preselect very carefully. All in all, still fun to use, and a good learning experience. Good Luck de WD4LNW.
Thanks for watching Phil. Yeah, it's going to be a nice long one. I'll work on it a bit once a month or so and slowly evolve it into a solid working radio of some type. I'll be tackling that preselector next time, try to get it tamed down a bit.
Kevin, I just found one of these at a hamfest 10-5-24. I have similar troubles with it..... preselector the same as yours, Microphonic, some kind of mod under the audio chip etc. Dave KC3AM
DE KD5SMF; I own a HW7 & HW8 and neither one are operational. I tried to replace the finals transistor on the 7 because I had Identified it as a bad component. I couldn't find an exact replacement for that one and installed something close to what Heath had in the original design but it smoked when I powered it up. Haven't worked on it much since. I do want to restore the radio back to original configuration. As for the 8, I haven't had much time to even chase sparks on it but likewise want to restore it as well. Hope your vid's on the 7 may help. 73's KD5SMF
Will intently watch vid's on this rig. I built the HW-9 prior for my first rig which is probably why I like QRP so much now. I purchased the HW-7 and HW-8 built by another ham at 2002 FDIM.
The HW-8 was my first rig, built it from kit form and made hundreds of contacts on it. This 7 is going to be an interesting project. I'll work on it from time to time, so this will probably be 4 or more vids.
The ground traces are connected at DC. Maybe not at RF. Although I would not expect this type problem at HF frequencies. I once had to work on a new board (new layout of an existing design). A UHF telemetry receiver. Dead as a doornail. After I drilled a few small holes and shorted the top ground to the bottom ground in 3 or 4 places, the thing came alive. To this day I don't know how I figured out where to add those connections. But, your trace shorts remind me of that experience. Given all the talk of how poorly the HW-7 was designed, this doesn't surprise me though.
You are right that thing is a mess ,I just heated up a trace to much trying to remove a old wax capicaitor,and the cool trace lifted up ,so I cleaned under the foil and super glued it back down,I hope it will stay when I have to solder a broken wire back,I also order some cool copper tape in several.sizes just in case,have you ever use foil tape to fix a trace before? I have but I figure it wouldn't hurt to have some cool tape around.
In high gain circuits at RF, bridging across meandering ground tracks is sometimes necessary, to reduce feedback causing self oscillation. However, I doubt it is necessary in an AF section, unless some device there ALSO has excessive gain at higher frequencies! Substituting with a "wrong" transistor can often cause this.
Look at KC9ON sale site on eBay (Possumlodge). He is my HW guru in N Michigan and has rebuilt my HW 7, 8 and 9. He offers a solid state replacement for the antenna change over relay, an ln386 audio amp board, and other almost drop in fixes for the venerable HW QRP series. Thanks for taking this project on as I will follow it diligently to learn about one of my favorite rigs of 1973, the year I married and got back into ham radio. Dave K8WPE
Thanks for watching Dave, and thanks for the info. This project will be spread out a little, I might only dig into this rig once a month or so. I'm still not sure if I'll restore it, or rebuild the board into some new enclosure. I've had, in the back of my mind, the idea to make some 'steampunk' hardware thing. This might be a good board to use for just such a project.
You should get lots of contacts with it. I made lots on 20 cw, including from Europe to the US, on my HW7 in the 1980s. I've still got mine. Needs some new OP transistors.
It almost sounds like the preselector stage is oscillating, rather like a regen circuit or something??? Looking forward to your progress on it. Hope you find a new front panel for it. It would be a really fun project to stuff it into a new case, though.73 de K7RMJ Frank
I've seen several front panels on eBay so you should be able to find one fairly easily. If it was me I would totally recap the radio especially you were going to keep it.
I own a HW-7 & HW-8 & neither one is working. I tried to work out the bugs in the 7, replaced resistors that were out of tolerance and tried to change out the final amplifying transistor but wound up smoking the unit when I applied the power supply to it. My 7 is in much better condition than this one in the video and I'd sure like to get it back on the air & functioning like new. DE KD5SMF 73
The HW-8 is a much better design. I've given up on the 7. It's just a terrible design. I had an HW-8 as a novice and it really worked well. I've recently aligned one for a local guy and was again impressed with it. I hope you can get the 8 working.
Between taking my courses for Aircraft Maintenance, and studying for the FAA exams.. I just don't have the time. The HK's were what I wanted and drooled over in the catalogs back in the day. As it is I'm a no code General but will get on to the 8 when I can. DE KD5SMF 73
problem with these was,, was a kit.,so called HEATHKIT so if you could solider was perfect. if you could not. then many cold solider joint. a head ache for a repair man. they have to resolider the whole rig. those traces on the board are from bad soliders and over heated the circut board..DE KI8BL
I picked up an HW 7 from flea market. Sadly the output section was blown up, I had hard time find the MPSU transistors. but i found them also had replace emitter resistors and the base resistor on outputs, The RF choke had burnt up ad was able to rewind on with old contactor magnetic core wire. I admit i had tried some 2SC transistors first of but that did work out well i needed the MPSU 05 . It seemed the zener diode shorted too on the power dc line, being it is 13 volt type. for all practical purposes I was going use 12 volt dc battery so if you wish one can install the zener but i choose to leave it out as the radio will work fine fro 9 to 14 volts. so after that i go power output. The receiver had a problem when turning the varible cap frequncy A STRANGE SCRATCHING NOISE WAS AMPLIFIED THE THE RADIO I had to take the VC out and soak the bearings in gun wash and use fize brass brush to clean and the re grease it and assemble and re install. this cured the strange scratching noise while tuning. That preselctor is pretty touchy that way it is. as most will say put a larger know on it it helps. its the design but one can live with it , preselector is touchy. So after many hours of work and parts I did an alignment by the manual, some what impossible get band edges perfect but it is very well tune in the CW portion of the band anyway. Funny old tube receivers i did have perfect luck alignments but some times LC circuit needs work as well so I left the HW 7 as it good on CW bands pretty close is good enough Time of truth,, with a vertical antenna and a north america contest on 20 meters I go California , Colorado , Kansas new Jersy, /vermont , Ontario, few other place, WOW that was amazing on 2 watts or so , I tried 40 meters but no luck guess 40 got be pretty good get out on 2 or 3 watts. but the little HW 7 is a usable rig and contacts can be made, it can run on a alamr type battery for hours and hours and hours , great emergency rig if oyu need one. just my exepriance on the radio 73 Tony ve4akf
Useful info on things to look for, thanks! Got an HW7 myself which is a similar near-basket case. Going to be a winter-time repair project for sure, before I can put it in the shack next to it's younger brothers (HW8 and HW9).
I have rebuilt a few HW-7's and Hw-8's. I enjoy the Hw-7 when it is working. The biggest problem you will experience when you are done is that Heathkit did not engineer any transmit offset in the Hw-7. That is why the RIT mod was popular in that it allowed you to zero beat the calling station and also adjust the receiver. I have good success on 40 and 20 meters...15 meters is usable if the band is really open, but 20 meter signals will appear on 15 meters unless you preselect very carefully. All in all, still fun to use, and a good learning experience. Good Luck de WD4LNW.
good little radios
Just amazing what a journey of repair it will be
Thanks for watching Phil. Yeah, it's going to be a nice long one. I'll work on it a bit once a month or so and slowly evolve it into a solid working radio of some type. I'll be tackling that preselector next time, try to get it tamed down a bit.
Kevin, I just found one of these at a hamfest 10-5-24. I have similar troubles with it..... preselector the same as yours, Microphonic, some kind of mod under the audio chip etc.
Dave KC3AM
Looks like you have your work cut out for you on that one. Be nice to see it live again. Thanks for keeping these alive.
DE KD5SMF; I own a HW7 & HW8 and neither one are operational. I tried to replace the finals transistor on the 7 because I had Identified it as a bad component. I couldn't find an exact replacement for that one and installed something close to what Heath had in the original design but it smoked when I powered it up. Haven't worked on it much since. I do want to restore the radio back to original configuration. As for the 8, I haven't had much time to even chase sparks on it but likewise want to restore it as well. Hope your vid's on the 7 may help. 73's KD5SMF
Will intently watch vid's on this rig. I built the HW-9 prior for my first rig which is probably why I like QRP so much now. I purchased the HW-7 and HW-8 built by another ham at 2002 FDIM.
The HW-8 was my first rig, built it from kit form and made hundreds of contacts on it. This 7 is going to be an interesting project. I'll work on it from time to time, so this will probably be 4 or more vids.
The ground traces are connected at DC. Maybe not at RF. Although I would not expect this type problem at HF frequencies. I once had to work on a new board (new layout of an existing design). A UHF telemetry receiver. Dead as a doornail. After I drilled a few small holes and shorted the top ground to the bottom ground in 3 or 4 places, the thing came alive. To this day I don't know how I figured out where to add those connections. But, your trace shorts remind me of that experience. Given all the talk of how poorly the HW-7 was designed, this doesn't surprise me though.
You are right that thing is a mess ,I just heated up a trace to much trying to remove a old wax capicaitor,and the cool trace lifted up ,so I cleaned under the foil and super glued it back down,I hope it will stay when I have to solder a broken wire back,I also order some cool copper tape in several.sizes just in case,have you ever use foil tape to fix a trace before? I have but I figure it wouldn't hurt to have some cool tape around.
side tone good for a boat horn !
In high gain circuits at RF, bridging across meandering ground tracks is sometimes necessary, to reduce feedback causing self oscillation. However, I doubt it is necessary in an AF section, unless some device there ALSO has excessive gain at higher frequencies! Substituting with a "wrong" transistor can often cause this.
Cold solder joint city!
Look at KC9ON sale site on eBay (Possumlodge). He is my HW guru in N Michigan and has rebuilt my HW 7, 8 and 9. He offers a solid state replacement for the antenna change over relay, an ln386 audio amp board, and other almost drop in fixes for the venerable HW QRP series.
Thanks for taking this project on as I will follow it diligently to learn about one of my favorite rigs of 1973, the year I married and got back into ham radio.
Dave K8WPE
Thanks for watching Dave, and thanks for the info. This project will be spread out a little, I might only dig into this rig once a month or so. I'm still not sure if I'll restore it, or rebuild the board into some new enclosure. I've had, in the back of my mind, the idea to make some 'steampunk' hardware thing. This might be a good board to use for just such a project.
Nice job! I am curious to see the trouble shooting of the myriad of little problems. 73 - AG7BW
Thanks for watching. I'll be working on it from time to time. Might be a few weeks between vids.
This was my first radio.
You should get lots of contacts with it. I made lots on 20 cw, including from Europe to the US, on my HW7 in the 1980s. I've still got mine. Needs some new OP transistors.
It almost sounds like the preselector stage is oscillating, rather like a regen circuit or something??? Looking forward to your progress on it. Hope you find a new front panel for it. It would be a really fun project to stuff it into a new case, though.73 de K7RMJ Frank
That's my feeling too, it's unstable and want's to oscillate. The preselector will be my next project on it in a few weeks.
Thanks. I am looking forward to it.
Hope you get it fixed up
Oh man, those hand drawn traces are like circuit porn :) 73s DE K8GLX
Yep, throws me back to a simpler time.
I've seen several front panels on eBay so you should be able to find one fairly easily. If it was me I would totally recap the radio especially you were going to keep it.
Had a new HW8 at one point
don't see part 2 or your other related video's?
I never made it. I ended up giving the radio away to another ham that enjoys the older rigs more than I.
Must have been an engineer. They are notorious for having bad solder skills. Kevin, you have some very cool videos.
Thanks for watching Wayne, more is coming.
ham are called amateurs for a reason.. as you are discovering !
Not sure what a Vector Graphic is but you can fine a jpg of the HW-7 dial scale here...
radiowb3t.homestead.com/HW7DialScale.html
"Bodge" How very Dave of you!
I was calling them bodges back in the early 80's.... ;-)
It's still an Australian term.
I don't think that's right. Old English perhaps? Middle Ages I think.
Kevin Loughin google it. Australian slang.
You know the Brits sent their worst criminals to Australia in the Middle Ages? You're both correct.
I own a HW-7 & HW-8 & neither one is working. I tried to work out the bugs in the 7, replaced resistors that were out of tolerance and tried to change out the final amplifying transistor but wound up smoking the unit when I applied the power supply to it. My 7 is in much better condition than this one in the video and I'd sure like to get it back on the air & functioning like new. DE KD5SMF 73
The HW-8 is a much better design. I've given up on the 7. It's just a terrible design. I had an HW-8 as a novice and it really worked well. I've recently aligned one for a local guy and was again impressed with it. I hope you can get the 8 working.
Between taking my courses for Aircraft Maintenance, and studying for the FAA exams.. I just don't have the time. The HK's were what I wanted and drooled over in the catalogs back in the day. As it is I'm a no code General but will get on to the 8 when I can. DE KD5SMF 73
Hello Kevin, Seen Many of your Vids May Need Your Help With Just This Item. Will get Back to ya.thanls. .73
Lighting/color is better. The W in KB9RLW on your screen is in focus, but your face isn't. :(
problem with these was,, was a kit.,so called HEATHKIT so if you could solider was perfect. if you could not. then many cold solider joint. a head ache for a repair man. they have to resolider the whole rig. those traces on the board are from bad soliders and over heated the circut board..DE KI8BL