| audio, gear, HK, vintage | 65 comments

Currently my favorite vintage receiver (that I've owned). This Harman Kardon 430 was made in 1975 and is still going strong today. After replacing some burned out lamps, it looks basically as good as new.

I've owned maybe a dozen vintage receivers over the past several years, but this one remains my favorite (hence why I've kept it). I bought it on Kijiji for $80 a couple years ago and have since given it a thorough cleaning. I've also replaced all of the internal lamps as several were burned out.

Made in 1975 and the little brother to the HK 730, it features a "twin powered" design, which means each audio channel has it's own individual power supply. Even though it's rated at only 25 watts RMS per channel, it has more than enough power to fill a room. I'm currently using it as the primary receiver for my turntable and to power my floor speakers—I'll write about those another time.


Replacing the lamps behind the tuner dial was ridiculously easy. The hardest part was actually finding suitable replacements (more on that later). The lamps themselves are a fuse type, which don't require any soldering to replace; just remove the old ones and snap in the replacements. You just need to remove a few screws to gain access first.

I also had to replace the tuner needle light, which you can kind of see in the blurry foreground in the above photo (I don't know why didn't I take a better photo while I had it all dismantled). You just have to pry up the two metal side flaps and lift the casing off. Once removed, snip the wires to the lamp and solder the new one in place.

I ended up buying the lamps from this site, which was the only one I could find that had both the tuner dial fuse lamps and the tuner needle lamp in stock. The tuner dial lamps were part number L-11 (0.25" diameter, 1.25" long, rated 6V and 250mA), and the tuner needle lamp was part number L-5 (0.12" or 3mm diameter, rated 6V and 35mA). You can also buy the fuse lamps from Amazon.

All better

Looking basically good as new! The next bit of repairs I might eventually tackle is replacing all of the capacitors with modern equivalents. There is an ever so slight hiss noticible when listening with headphones, and new capacitors might clean that up a bit—or so I've been told—as the originals are probably quite dry after 35+ years! I just need to practice my soldering skills first.


I had the same problem with the same receiver (HK 430)
it was not easy to find these fuse type lamps in France
i found them from e-bay from US (Tech Hi-Fi, Roseville, MI 48066)
very easy to replace
dial looking as new
Robert from France

Thanks for the write up. I just got a 730 last week, all cleaned up and sounds amazing. I have about 4 dial lamps out, dial needle lamp is out as is the power switch lamp. I will try the dial and needle lamps soon and research the power switch lamp later as it looks a lot more crowded down in that corner of the unit.


Many thanks for the excellent article.

I have an HK430 that I've owned for probably 13 years now, connected to a pair of Klipsch Heresy IIs that I've had for 20 years, and a Sunfire Sub that I've had for probably 5 years. I use them to handle the 2-channel audio on my widescreen TV in the living room.

They get a lot of use (12 hours a day) and the bulbs on the HK430 are now all burned-out. My question is, "How many bulbs does the unit take?"

I'd rather ask and then order the required number of bulbs so I only have to disconnect everything and take the receiver apart only one time (it's the proverbial rat's nest of wires under the TV with all the gear interconnected).

Thanks in advance!


Jason, I honestly don't remember how many fuse lamps it took. Looking at my photos, it looks like at least four, however I think there would at least one more possibly two. Plus the signal strength meter would be another of the same type.

Luckily all of the lamps are cheap enough that you can order more than necessary, so you are guaranteed to have enough for the repair plus some spares in case you need them in the future.

I checked the service manual again, and it shows there are six required. But it doesn't specify if it includes the signal strength meter. So I would get at least 7 to be safe.

You can find the service manual here - http://hifiengine.com/library/harman-kardon/…


MANY thanks for the quick, helpful response!

I will take your advice and order 7 of them, just to be safe.

Kind regards,


I also have a 430 and noticed that the #1 power transformer runs warmer than the #2 power transformer. #1 Xmfr has the secondary supply for the display lamps which are rated for .25 amps (x6 lamps = 1.5 amps). Heat is a killer for most gear so I decided to remove the lamps. Now both xmfrs run about the same temp and the display has a nice cool look to it with only the lamp in the pointer being on. Another option is to use LED's. This will cost more but it will help preserve this wonderful sounding little receiver which I'm listening to right now. Sweet!!!

I own one of these terrific receivers and would like to do two things that I need yr advice on please?
1) What's the best antenna to boost the AM signal using the H/K 430?
2) Want wireless speakers (so we can enjoy the sound anywhere in the house or outback)?
I do understand that wireless speakers aren't going to give the quality audio one expects (or that you all may get from higher end speakers)...so forgive me for asking about a lesser speaker. Don't mean to offend all the audiophiles out there!
Thanks for any advice you care to post.

Apologies for the late reply.

As for the AM reception, I would look into an external antenna. I am sure if you google for DIY AM Antenna, you will get lots of helpful responses.

Regarding wireless speakers, I don't know any specific models unfortunately. I imagine you'll need to get a wireless receiver that accepts speaker wire input (from the HK). I don't know if one exists.

I am guessing that any wireless speakers would need to be individually driven by built in amplifiers, meaning that none of the vintage goodness from the HK would even make it to your wireless speakers. You would effectively be sending the analog signal from your HK into a wireless receiver, where it's converted to digital, then beamed to the speakers, then converted back to analog by each speaker's built in DAC, then finally amplified using each speaker's built in amp. Any benefit in using the vintage HK would be destroyed.


Great site inspired me to fix the lights on my 430. I'm relatively new to this type of endeavor, but I ordered the parts got the fuse lamps in and amazingly removed the face and soldered in a new indicator lamp. However to get the face off I had to remove the tuning knob which required loosening the tuner string ... however this is where I'm now stuck. I unscrewed one of the white pulleys to create slack but I cannot seem to get it back in? What was your plan of attack? Did you re-string from scratch? Any guidance is appreciated.

I find it strange that you had to touch the tuner string to remove the knob. In every receiver I've ever touched, the knob just pops off without issue and the HK430 was no exception. It sounds like maybe your unit was modded or something. Not sure.

I've never done a tuner restring from scratch, but I have restrung the original a few times on other units. It's always a major pain in the ass. The service manual should have a restring diagram in it.



In retrospect it appears I over complicated removing the face on mine. I was a bit gun shy with applying enough pressure to remove the external knob and ended up removing the entire assembly from the inside ... Not recommended. I just acquired a 730 that needs a similar overhaul and plan to take the simpler approach for sure. Thanks for the reply.


I just changed the bulbs on my friends 430 and then tried it with a pair of my Totem Mites. It sounds very similar to my same era NAD 3020, but sure looks a lot better! The 430 is very well built, IMO and these are worth saving.

You can find the "fuse lamp" 6.3V 250mA at "E44" in Nantes (France), for about 1.2€ each.
the indication 150mA is a mistake, it's some 250mA!!
I restored my HK 430 this week (replaced all the chimical condensers, and all the lamp..

hey, cool page....just bought a used HK430 and i'm super stoked...but got everything hooked up and noticed my speakers were crackling every time i changed the volume, after searching on google, most sites say that i probably have a "dirty pot" and an easy fix is turn the unit off and rotate the volume knob back and forth about twenty. i did as google suggested but now i believe i have made the problem worse.
any thoughts?
should i open her up and physically clean the pot?
any advice would be greatly appreciated.

Bram, you only did half of the job. You need to buy a spray can of plastics safe contact cleaner, and physically spray it inside the knob, accessing it from the inside. There should be a small opening in the back of the pot. Once sprayed, turn the knob back and forth a bunch of times. Repeat if necessary.

hey Jeff, thanks for the reply...i think i prematurely left comment, should have read just a little more..
I bought a can of deoxit and cleaned all my pots except the Function knob (FM/AM/PHOHO/AUX).... they work beautifully now.

my new issue seems to be pretty sporadic, sometimes the left or the right speaker's sound seems to die out and get very tinny...i check the the rear speaker inputs and every thing seems to be fine there.....but when i just ever-so-slightly move the Function knob a tiny bit left or right, but not to the point of actually changing the mode, i get full beautiful sound.
Does that mean i should clean that switch?
and should i clean it the same way i clean the other pots?

and is there any way to refurbish the top black metal? mine seems to have a little discoloration?

thanks so much for your help!

Yes, in addition to all of the pots you should also try to clean all of the switches, since they are susceptible to the same degradation over time. If moving the function knob fixes your problem, it sounds like it should be an easy fix.

hey jeff. nice site. i have a comment for ron, on restringing the hk 430 (yes, i know it's an old post :) ).
ron, reassemble your receiver, minus the dial string of course. now, set your pointer to midway on the dial. set the round molex (nylon?) disk attached to the front of the variable capacitor (those fins you see behind the dial pointer, about 1 1/2 inches behind it) so that the fins are at the half-way point between totally open and totally closed. start your dial restring at the inside point of that white disk on the front of the var capacitor. wind clockwise, only one revolution and when you get to the top of this one revolution, send the string off to your right, to the first small wheel, then in towards the front of the receiver to the second small wheel, then across to the pointer, to the front small wheel on your left, back to the inner small wheel on your left, and finally in towards the white disk, entering the disk in the groove in front of the groove you originally left it from, around one revolution clockwise, and tie off at that point. whew!
hope this helps (or sufficiently confuses LOL)

Hey Jeff... I'm downsizing & selling my HK430. Do
can you recommend a good site to post it?
Everything works great. Kinda hate to part w/it.

Forgot that darn tuning shaft. :)

Lynn, I sell all of my gear on Kijiji, which is like a Canadian craigslist. All depends what's available in your area. I avoid eBay because I hate dealing with shipping.

Hi Jeff thanks for your site. I just got myself 430 and I'm doing the very same thing. Has anyone out there changed the power light? Mine is gone and it seems difficult to remove.

I am planning to take out the blown lamps and to convert them into LEDs by simply soldering a small 3 mm LED and an in-line resistor across the fuse bulb. I will post a pic when I am done cheers

What is the lamp type for the power switch and the stereo light?


I just replaced my lights with LEDs. It took a little more time than I expected since I was unaware the main bulb circuit is AC. I made little replica bulbs using plastic drinking straws and bicycle brake cable ferrules (both of which luckily I had lying around). Inside each of these I placed a 3mm warm white LED with an in-line resistor.

Simply replacing them results in flicker due to the AC. It's not that obvious but I found it annoying. So I decided to rectify the AC circuit. This was pretty easy - 3 components, a bridge rectifier, smoothing cap and a 7805 regulator. You could probably even do without the regulator as the total current required by the new LEDs is so small (circa. .1A) that a 1000uF cap would probably smooth it fine.

I measure about 4.5 v coming out of the regulator (the 6V AC after rectification is probably not enough to get it up to the stated 5V) - but that was fine as it helps the LEDs to be not too bright. I had to darken the tuning needle lED with a sharpie as it was noticeably brighter after the replacement but the rest look fine.

Just to confuse matters the stereo indicator light is rectified (fed from rectifier A).

As I was doing this I noticed that half the 6V feed to lighting circuit (the green wire) is wired to a orphan contact on the Rectifier A board and then just joined to another length of black wire before threading up to lights. A design change? Maybe they were planning to rectify that light circuit and then changed their mind because of the current draw? Anyway I too the opportunity to clean up the wiring a bit.

Very pleased with the results and the box is much cooler now - so I do recommend it. The only tricky thing is working around the dial string with the soldering iron. I nearly burnt mine through !!

If anyone wants more info or pictures I will post them.

Hi Stephen, I would be grateful if u could publish your pics. Regards, Pier

Here are some photos from LED project.


Sorry - some problems with sharing the Picasa album. Try this one...


Seems to be some kind of problem with links on this site. When I paste the website URL it loses the colon in the link. If you want to see the pictures click on the link above and then manually insert the colon after https. Sorry seems to be a bug with the software hosting this blog.

I've ordered the dial tuner bulb off of eBay. The bulbs are 6v 35ma and .12 in diameter. Can I use the bulb for the stereo light? What about the power switch? The seller had them in packs of five, so I have extra.

In response to my previous post, the same bulbs for the dial tuner were soldered in for the stereo lamp, and everything seems to be working. My last lamp is the power switch, and then everything will be working. eBay sells a 5 pack for $5 or something like that.

I just finished led mod for my friend´s 430. I ordered cheap ebay 12V DC fuse leds (10pcs for cars etc) about 5€´s, rewired 12V power from rectifier A board. For pointer light I used a 3mm standard yellow led. For power indicator a 5mm bright white led, both with resistors. For stereo indicator I soldered a white led with a resistor, a little smaller than 5mm? Tuning/dialing panel is not yet installed back, but signal meter light looks nice and bright.

Your LED modification for the 430 dial pointer interests me. Did you have to use a dropping resistor with the LED, or did it sub directly? If you used a resistor, could you share the ohms value with me?

I cannot recall certainly what was the value, but indeed you need a resistor.

Be my guest.
I just now recalculated; it must be a 680 ohm resistor.

A standard 3mm yellow specs about:
-drop voltage 2-2.4V
-current 16-18mA

Use calculator (for example ledcalc.com)
put values:
Supply voltage: 12.1 (mine gave 12.1V from the rectifier board)
Voltage drop across led: 2.2V
Desired led current: 17mA
How many leds connected: 1

It gives the nearest suggested value: 680 ohms. (Exact value 582 ohms.)

For my opinion the standard yellow 3mm led is a little bit dim, but works on dark.
Actually the color is more like orange. I had those yellow leds lying around, so I used it.
You can use or try a brighter one (white, yellow or anything you like). Too bright might not be good as well. Check the led specs and use the calculator. Very easy.

12V fuse leds I used worked great with tuning dial installed.

Thanks for the info, I'll give it a try. I was also thinking of taking the burned out tuning dial fuse type bulbs and using the two end caps, small lengths of perforated circuit board material and mounting green LEDs and dropping resistors. Would you know what value of resistors I should use?

It depends on what kind of green led you will use (ultra, super bright, standard etc). You need to know the led specifications; the drop voltage and the current values. Brighter ones will use more current. Those values differ from size, color, material and brightness of a led. Using the led calculator gives the resistor ohm value. All the fuse bulbs are in parallel, so every green led will need a resistor, like the possible pointer and the power leds. Ask from the seller or check the datasheet, some web pages might have that info too.

"Led current:
20mA will work for most regular leds.
Superbright leds can go from 30mA up to several amps. "

Mine rewired DC 12V version differs from the original HK430 wiring, which uses AC 6V.
Mine led-version would not work with AC 6V. I ripped those AC wires out and rewired from the rectifier A. If you use DC power the polarity must be taken into account.

Actually the rectifier A will give 12.6V according the schematics. Mine HK430 gives 12.1 volts, I suppose partly due HK mains is set now for 240V from 220V. We used to have (in Finland) 220V in 1970´s but was raised to 230V in 1980´s. So mine (serviced) HK430 works 10 volts under. I guess my friend´s amp is made in late 1970´s.

Hi Jeff,
I just received a HK 430 this week from a seller here in Jakarta. I paid US$275 because it is a nos unit and after reading your blog, I just couldn't resist. This is my first vintage and I love it.

Everything works perfectly except the volume crackling sound. I wanted to use contact cleaner to clean the volume pot but the seller recommended me to just turning it many times for a couple of weeks.

The unwanted sound did became less and less but it's still there. I figured this unit is basically brand new and was sleeping for a long time and needs exercise now (that makes sense.

Do you think I should just spray the insides just to be sure? And what happens to the parts of this kind of amp that has not been used for this many years?

This crackling sound is usually caused by the carbon element wearing down from use and some carbon residue particles left on the surface. Turning the pot back and forth can temporarily dislodge those loose residue particles, but what I have experienced is that they usually come back to some degree again.

I would suggest flushing the pot out with a silicone loaded contact cleaner that's safe on plastic, or using stabilant 22 diluted with rubbing alcohol and shoot it into the pot with a syringe. Some may suggest changing the pot, but I would only suggest that for badly worn out pots.

I have a 430 that I bought new way back when. I am having a few issues. When I turn it on I get really, really loud cracking sounds from the speakers. The tuner does not lock on to FM stations, even with an external antenna. Finally, when I plug in a turntable nothing comes through the amp regardless of whether I plug it into the turntable or any other jacks. I am so frustrated I am thinking of selling it. Suggestions?

Needs probably recapping, contact cleaning and a 300 ohms antenna. Check out possible bad solder joints.

Great site!

I've also got a 430, for some time, and it is great.

When it works. It has a problem, that is, one speaker channel tends to cut in and out. This is worst with the turntable, but sometimes happens with the other functions as well. If you jump on the floor, sometimes it cuts back in, but then might cut out again. And, sometimes it works fine. Seems the humidity/temperature has some effect.

A few years ago I had a guitar amp specialist clean it out, he said the issue will return (it did) and is basically not fixable.

Any recommendations? I'd really like to keep the unit in play.

Have you tested the second speaker terminal? HK430 has two terminals; system 1 and system 2. It has two switches as well. Use contact cleaner spray for speaker terminal switches like the amp specialist probably has done before.

You may want test with headphones, if the problem exist as well. In that case the problem has nothing to do with switches.

P.S. Contact clean all the switches. Most likely the input source switch might cause the trouble like the speaker terminal.

Hi Jeff!
I have one of these, and am planning on using the b channel to run wires to a pair of outdoor speakers. My question is about using a power tube amp after the receiver to the wire then to volume control and speakers. Do you know (as I was not sure about the results of my research): are the speaker outputs able to be amplified, and if so what sort of amplification do you recommend? I am getting 50W outdoor speakers, and running th eline approximately 50 feet (with navigation of walls etc).

Thanks for any help you can offer!


Hi Jeff!

Thanks for your post! I own a 430 but it sadly came without a power switch (not just the lamp but the actual entire switch). I was wondering if you or anybody else knows where to get one?

Thanks in advance!


@Felix - I have a 430 that with a dead left channel that I am replacing with a 730 from which I can part out the switch.

@Sebastian that would be superb! Although, did you check all the fuses in your 430? Replacing them fixen my dead channel issues.

@Felix...no luck

Hello Iamthejeff
I have same HK 430 Twin. It needs cleaning and a lamp. Do you do repairs or do you know of someone in Ottawa who is good. My older brother bought it new in 1975 and I have had it since mid 80s. Unused for last 12 years but not forgotten !

Vintage Audio Repairs in Ottawa area......J R Perry Electronics on Wellington St, Ottawa, Centek Electronics, St Laurent Blvd.Ottawa.


Where do you snip the wire for the tuner needle lamp? I purchased the 6V 35mA L5 bulbs on ebay. The ones I purchased have a 6" red wire from the bulb to open wire at the ends of the two red wires. Do I solder the open wires to the curly clamp that holds the wire behind the unit? A friend is going to bring a soldering iron when I am ready.

Ethan, I just snip the wires anywhere and splice the new ones in place, making sure there's enough length for the needle to travel across the entire tuner dial without creating any tension.

I just picked one up last weekend for $50 at a garage sale. Thanks for the info - my lights were out too. The fuse lights I can handle but a little worried about the dial bulb.

That's the problem is I cannot find a way to get that faceplate off to get to where the replacement bulbs will go for the dial

My fuse bulbs will arrive in a few days - so I have not opened the unit up yet. If it's tricky to get to the fuse bulbs, any help would be greatly appreciated. Thanks

OKAY, i just now took the faceplate off and found the spot where I need to fuse the bulb in for the dial lamp. Problem is, the bulb I am replacing is about half the size of the one that I received from the vendor I purchased from. Where did you buy yours from??

How can I get the VU meter to work ?
It`s technically OK but not working ...

How do you know what year it is?

Hi Jeff
Thanks for this awesome article. I just got myself the HK 430 and it sounds great. I need to put in a new tuner needle light - do you know what the original color was? And I thought of putting in some LED's as the tuner dial lights seems a bit low, should I go for some green LED's or just white? Or maybe just plain tube lamps? What do you think...

Greetings from Denmark.

/ Jakob

Jakob, I just use regular incandescent bulbs which are somewhere between white and yellow naturally.

It's an old post, but it's still turning up in google searches and it's still helpful.

I found fuse-style LED lamps here:
And the mini-lamps for the power button, radio dial, and FM stereo indicator here:

It's all working great, thanks!

Thanks Jeff!
I was wanting one of these, and your article made me willing to jump on a $90 unit with no lights working (except power). Friends LOVE the sound; using with with a Nakamichi Music Bank 1 CD and airstreaming from my laptop.

I can confirm that mine took 6 LED fuse lamps. I also bought my lamps from Vintage Electronics. However, I'm having a hard time finding the mini lamp for the tuner needle (ebay, amazon, google search); the 8v LED sub-mini lamp from Vin.Elec. is too big. I'm not really using the tuner much—I'm streaming radio (and computer music) into the Tape Monitor input—but it would be nice to have the tuner needle lit up, if anyone knows a good source (end of 2018 now...)

Just bought one of these for $50. Been wanting one and took a chance. So far, it's working well with headphones, but haven't hooked it up to speakers yet. I've got it opened up, cleaning pots, interior dust, etc. And dial lamps ordered.
However, I find that the tuning meter flexes very little, even on strong stations, and the stereo indicator light never comes on. Looking for ideas to check it out.

For the dial pointer light, buy a or some "Grain of Wheat" bulbs on Amazon or Ebay. They should be small enough to fit.

Thanks for the links on the lamps. Found out I didn't need them. Cleaned the pots, replaced all the dial lamps except the stereo indicator. Put a simple dipole antenna on it, and it gets great reception! All lights lit!