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Found Grundig w/ Blast City Tube

Just talked with the Blast chassis owner, he might sell it to me if the cost of repair is too high. This Blast needs a complete overhaul, so I had to give a high quote for parts etc.
Anyways he's thinking about it.
Here's some pics of the POTs, they have filament glow but no picture. I'm surprised they even get that, half the resistors are corroded to crud.
Probably a POT has gone open and eliminated any screen possibilities.

So if I end up buying this chassis, do I need the control board and the cab, or is there a way to attach inputs to this chassis? I should really be looking at how to use a Blast chassis properly.

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Mrhide said:
What do you want to run on the Grundig? if you want to run consoles, get a D-Series and *ahem*, offer the toshiba tube to somebody with a spare ms-29 chassis :) :)
Click to expand...

C'mon man a D-Series? I'd be downgrading a lot. I'm just hoping to run a MiSTerCade Jamma Kit in to it. I already own some high quality monitors. Anyways I won't bore you with my setup, I'm just testing the waters.
 
The Grundig chassis looks like it's working and displays a nice picture. Unless you actively have a Blast you need to repair, I wouldn't swap the chassis for the Nanao. The MS293x is notoriously unreliable junk anyway. I'd just service the original chassis and keep it as a nice rare display. :)
 
Maybe you're right. Just got hopeful to have a monitor that takes care of 15-31khz.. but it's a bit ambitious considering the majority of my gaming is done on 15khz content.
 
trashedcabs said:
The Grundig chassis looks like it's working and displays a nice picture. Unless you actively have a Blast you need to repair, I wouldn't swap the chassis for the Nanao. The MS293x is notoriously unreliable junk anyway. I'd just service the original chassis and keep it as a nice rare display. :)
Click to expand...

I agree with @trashedcabs. Get the Grundig chassis repaired. We tend to shelf queen the MS293x around here, but theres equally a ton of threads where we're fed up with them.

Post some screens of that baby when its repaired and firing on all cylinders!
 
Nice to see a Euro made TV with a proper A68 crt in it! Pretty much everything you see here (i'm in the UK) of that sort of size uses an A66 crt - which is fine for Euro made stuff like Hantarex monitors etc. but not Nanao and other stuff like WG monitors. It's pretty rare here to see a crt TV with an A68 crt!
 
Rg111 said:
@Slypty Do you have a similar menu on your display? I dig it.

View: https://m.youtube.com/watch?v=TZd2sCCRom4
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Thanks for sharing that! I just ordered the TP760 from Germany a few days ago, so I can't check out what menus I have. In fact, I can't even adjust brightness yet, only volume and inputs. I'll report back once the remote arrives, thanks for sharing the vid I'd like to try it


I was reading the service manual last night, it's definitely got some odd features. All tuning of geometry is programmed through a chip, which has a back up if its' fried (not sure how) but it can be re-enabled from dead if the logic goes, and rewritten by booting from ER mode. Anyway, the geometry is saved to a logic IC from factory. There's no adjustments in this set, only A+ voltage adjustments. To set geometry basically you rewrite the IC that's pre-programmed with the same info, after you adjust the A+ voltage.. It tunes things via some sort of oscillation method I've never heard of. Quite funky. My geometry is actually great, however the dynamic focus is starting to spread out.

This thing already looks amazing. I changed a few caps (mainly just on the modulator board, they were mostly reading high ESR) but resistors are clearly outstanding quality, often reading exactly what they need to be. Today I'll take a close look at the flyback and voltage, since I have breathing when there's a noise/snow background. I think the voltage isn't steady. Also need to try a different step up converter in case mine is crap.
 
I like how it says "Design by FA Porsche" on it.

I had no idea Porsche was designing CRTs, especially with Toshiba tubes in them. Looks like he knew what was up.
 
Found this Porsche chip on the LCD board, it was behind the chassis under the tube. Not sure what Porsche had to do with a TDA (vid processing?) IC, a little odd.
 

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Slypty said:
Not sure what Porsche had to do with a TDA (vid processing?) IC, a little odd.
Click to expand...
It's probably to notate that its for the Porsche line of products.

It could be an on screen menu they specifically used for the Porsche line or something like that.
 
Well that was a dusty debacle. I couldn't leave this Grundig chassis all full of dust if it's going to be a daily driver. It's actually a very cool design, a Philips IC with a Blast tube is a very nice match. Porsche IC might be behind the service menu options. Very bright and amazing scanlines. The only issue I'm having is some moire, and even after the recap I'm still getting breathing on a static background, but that is likely to be Bright/Contrast being too high.

The best part about this set is the Service Menu. There's an embedded geometry test pattern, and some easy alignment integrations to get the white balance and focus just right, and it's all digital. The only manual adjustment is done for the A+ voltage.

I opted to spend a few extra bucks with the Nichicon can caps, they're rated 135deg. low impedance, these are 620uf 80V Caps. Originals were 600uF 63V, I replaced 2 out of 3 that had strayed to about 735uF. 620uF was the closest available value. The one remaining Unicel capacitor read exactly 600uF, 0.5Ohm ESR and 1% VLoss. Why replace that? Also check out the quality of the grounding plate on this thing. Caps did need replacing for the most part, some I left in since they were better than brand new in some cases.

I'm still waiting for the remote to fix the horizontal shift and probably needs a bit of color calibrating, but after playing a few hours the results are encouraging. I'll wait for the remote to post screenshots after adjustments are complete.

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I will soon share my research here.
I have the same TV since a while and In process of swapping the chassis with 2930. The grundig yoke is not compatible, I've measured with LCR even if not so bad.
We have in Europe Grundig everywhere, and they use a lot of Toshiba tubes. I've been able to found KZN and LBT ones. Also the same model as we found in NNC, but on a consumer set with native compatibility with 480p ! It's the xentia model, I use it for Naomi.
We also have Toshiba TV set with Toshiba tubes that match with NAC curvature of the MS9.
I've been able to build a list of TV where we can found those tubes. I'll share this soon 👍
 
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Must be nice to have Grundigs with Toshiba tubes around, i don't think any consumer sets really compare after playing on the Grundig. I'll take a few pics tonight, I got in to the service menu and made some adjustments. Does yours' have any moire? Do you know a way to cancel it out?
iori said:
I will soon share my research here.
I have the same TV since a while and In process of swapping the chassis with 2930. The grundig yoke is not compatible, I've measured with LCR even if not so bad.
We have in Europe Grundig everywhere, and they use a lot of Toshiba tubes. I've been able to found KZN and LBT ones. Also the same model as we found in NNC, but on a consumer set with native compatibility with 480p ! It's the xentia model, I use it for Naomi.
We also have Toshiba TV set with Toshiba tubes that match with NAC curvature of the MS9.
I've been able to build a list of TV where we can found those tubes. I'll share this soon 👍
Click to expand...
 
A few screenshots. Any tips on getting rid or lowering moire?
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I'm sorry but I can't help with moire effect, the one I have is not working, I have it only for the tube which is in perfect condition and I will adapt a ms2930. This TV set is 100hz and not good for 15khz.
But I have the 410 reference with the LBT tube. I've used it for the 31khz which is native and no moire effect on it. Didn't test 15khz as it is 100hz.
Maybe you will have better luck with service menu ?
 
iori said:
I'm sorry but I can't help with moire effect, the one I have is not working, I have it only for the tube which is in perfect condition and I will adapt a ms2930. This TV set is 100hz and not good for 15khz.
But I have the 410 reference with the LBT tube. I've used it for the 31khz which is native and no moire effect on it. Didn't test 15khz as it is 100hz.
Maybe you will have better luck with service menu ?
Click to expand...
I can minimize the moire effect, the only way I found works is find a decent contrast and bright level, some combinations will eliminate it. You must have the DPL version which is 100hz, the TOP version I have is 15khz. I think the moire may be partially due to an incorrect A+ voltage, but I'm having difficulty figuring out where the variable resistor is to adjust it properly.
 
I have the IDTV version which is sadly 100hz. That's why the chassis is already in the trash.
Tube remains perfect 👍
 
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