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    Marantz 2270 fm tuning problem

    Not sure I fully understand the issue but before you untie anything, open up the unit and see what's being obstructed. I suspect the position of the pointer relative to the start/finish in the diagram above might be off enough to bump into one of the pulleys. Or, the pully at step 4/5/6 may be...
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    2275 Seattle area looking for tech

    I would call Hawthorne Stereo and ask who they'd recommend. It's not something they'll take on but they might point you in the right direction.
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    Thoughts on 2270/2275/2285/2285b/2325

    I've had a number of units, all recapped. 2010/2225/2226b/2230/2265B/2270/2275/2285BD. I went through a handful of 2270s and 2275s when I was restoring them for fun. All that is left is the 2285BD because I moved on to modern equipment and I purchased it last. Looking back I wish I would've...
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    2285BD FM Left Channel very weak

    As the title suggests, I'm having one weak channel when listening to FM (left channel is weak). It's only on the FM 25uS input for the Dolby adapter. The normal FM input seems to work fine. If I push right mono, both channels come in equally strong. If I push left mono, both channels come in...
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    Another 2275 FM Stereo Issue

    Hey Tom, I regret to inform you that you've been helping a fool. I centered the tuning meter and didn't notice any change in voltages. I triple checked solder joints on the bottom. All fine. I started pushing at components on the top of the board and found a broken lead on a brand new...
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    Another 2275 FM Stereo Issue

    Thanks, Tom. H309B = 80mV H311B = 0.3V-0.5V... it moves around a bit H314B = 0.64V H315B = 2mV
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    Another 2275 FM Stereo Issue

    At peak signal strength, H309C stabilizes around 120mV on multiple stations. In between stations, it drops as low as ~25mV.
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    Another 2275 FM Stereo Issue

    Hey Tom. Monitoring H311B, there are a few stations where I can get it to appear to turn off. With high signal strength and FM tuning a little right of center, the voltage drops to just over 100mV, but most of the time it's above that. Sometimes I can get it to drop to ~60mV (similar to what...
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    Another 2275 FM Stereo Issue

    Just the man I was looking for! I don't know how much this will help but here are all readings for H301, 308, 309, 311 when tuned to the strongest signal I can get. H301 D - 5.7V S - 5.7V G - 6.3V H308 B - 0.6V E - 13mV C - 60mV H309 B - 57mV E - 13mV C - 90-100mV it is jumping around a bit...
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    Another 2275 FM Stereo Issue

    Thanks, Doc. I should've mentioned it's been cleaned. Signal strength seems pretty good and doesn't sound overly dirty.
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    Another 2275 FM Stereo Issue

    I have a 2275 with no FM stereo. The bulb is fine. I am tuned to a station with signal strength meter about half way. I don't think I'm hearing stereo on the 2275, but my 2285B receives a strong stereo signal on the same station without issue or an antenna. Before the recap of P200 and P300...
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    Recapping 2238B & 2265B, orange Nichicon caps?

    I have recapped a 2285b and 65b. On the 65, I used all silmic 2 and wima. Even in the power supply. It sounded truly fantastic after some break in. I replaced a few transistors as well. On the 85, I used PW in the power supply, lots of silmics, and KLs to replace the orange ones. Replaced...
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    2285BD Power Supply Voltage Issues

    Yeah the biggest differences so far seem to the preamp. Any idea what could cause the Voltages to be so far off?
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    2285BD Power Supply Voltage Issues

    Common cathode measures 36.0V. For what it's worth, Q816-Q818 are original. No major problems but to be honest it doesn't sound very good. I'm not particularly experienced but I would think the voltages here are too far off? Thanks to you both.
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    2285BD Power Supply Voltage Issues

    Thanks for the response. I've checked the solder pads, traces and joints for 811 and 812 and everything looks good. In terms of the orientation, they're oriented in a way that matches the printing on the board and the schematic. In other words, the emitter of 811 flows to the base of 812...
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    2285BD Power Supply Voltage Issues

    I believe I have an issue with my 2285BD power supply. The layout seems identical to the 2285B schematic, except that C804 was a 47uf/50V instead of the 10/50 listed in the 2285B service manual. Filter caps are original. I have replaced all electrolytic caps and the relay in the PS. Transistors...
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    2285BD - No output on right channel

    I would get a really faint and distorted signal when tapping them. So probably a broken lead or bad solder joint at the base that got worse when I was working on the board. I'd already decided to replace them so it wasn't a big deal. Glad it's resolved. This one is coming along nicely.
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    2285BD - No output on right channel

    I replaced the 2sa798 transistors in the preamp and got both channels working.
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    2285BD - No output on right channel

    Yes, the transistors are now KSC1845 and all are oriented correctly. I'll start checking voltages as I have free time.
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    2285BD - No output on right channel

    We're on the same page. The amplifier section is fine. The Pre-In jacks - I will clean them more, but this unit has the internal connections anyways and the symptoms persist with or without cables. All the other switches have been cleaned multiple times. On the preamp board, yes I have...
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    2285BD - No output on right channel

    Thanks! 1 - Right channel is dead when I plug in a source. 2 - Correct. I believe the problem lies before the amplifier 3 - When I switch cables, the dead channel switches as well. 4 - This amp has Mono L and Mono R. I can push either or both and still get audio. I haven't connected the...
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    2285BD - No output on right channel

    Hi experts, I've been bringing a 2285BD back from the dead. When I got it, there was terrible distortion from both channels and no relay click. I've restored the power supply and amplifier, which dials right in. When I play a source direct into the amp, I get clean sound from both channels. If...
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    Marantz 2010 - refresh

    I restored one of these a few years ago and it sounded great. Punched way above its weight class. I miss it!
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    APT Holman Preamp Questions - Which Op Amps to use?

    Thanks, this is great. I replaced a few films in the phono and will likely continue to upgrade caps and resistors. For now, I've ordered a bunch of OPA2134. I read your other thread as well and for the sake of future APT searchers, here's HalfApt's recommended resistor mods: "So I plan to...
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    APT Holman Preamp Questions - Which Op Amps to use?

    I'm currently working on an APT Holman preamp. I have replaced all the electrolytic caps and it is sounding good! A lot of people recommend replacing the op amps. The originals are TL072 and I've seen a few different recs for replacement, such as OPA2132. I've never replaced op-amps before...
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